Q1: Solve the following equations:
(a) 10p = 100
Ans:
Now,
We have to divide both of these sides of the equation by 10,
Then, we get,
= 10p/10 = 100/10
= p = 10
(b) 10p + 10 = 100
Ans:
Firstly we have to subtract 10 from both sides of the following equation,
Then, we get,
= 10p + 10 - 10 = 100 - 10
= 10p = 90
Now,
We have to divide both of these sides of the equation by 10,
Then, we get,
= 10p/10 = 90/10
= p = 9
(c) p/4 = 5
Ans:
Now,
We have to multiply both of these sides of the equation by 4,
Then, we get,
= p/4 × 4 = 5 × 4
= p = 20
(d) - p/3 = 5
Ans:
Now,
We have to multiply both of these sides of the equation by - 3,
Then, we receive,
= - p/3 × (- 3) = 5 × (- 3)
= p = - 15
(e) 3p/4 = 6
Ans:
First, we have to multiply both of these sides of the equation by 4,
Then, we get,
= (3p/4) × (4) = 6 × 4
= 3p = 24
Now,
We have to divide both of these sides of the equation by 3,
Then, we get,
= 3p/3 = 24/3
= p = 8
(f) 3s = - 9
Ans:
Now,
We have to divide both of these sides of the equation by 3,
Then, we get,
= 3s/3 = -9/3
= s = -3
(g) 3s + 12 = 0
Ans:
First, we have to subtract the number 12 from the both sides of the equation,
Then, we get,
= 3s + 12 - 12 = 0 - 12
= 3s = -12
Now,
We have to divide both of these sides of the equation by 3,
Then, we get,
= 3s/3 = -12/3
= s = - 4
(h) 3s = 0
Ans:
Now,
We have to divide both of these sides of the equation by 3,
Then, we get,
= 3s/3 = 0/3
= s = 0
(i) 2q = 6
Ans:
Now,
We have to divide both of these sides of the equation by 2,
Then, we get,
= 2q/2 = 6/2
= q = 3
(j) 2q - 6 = 0
Ans:
Firstly we have to add 6 to both the sides of the following equation,
Then, we get,
= 2q - 6 + 6 = 0 + 6
= 2q = 6
Now,
We have to divide both of these sides of the equation by 2,
Then, we get,
= 2q/2 = 6/2
= q = 3
(k) 2q + 6 = 0
Answer :
First, we have to subtract the number 6 from the both sides of the following equation,
Then, we get,
= 2q + 6 - 6 = 0 - 6
= 2q = - 6
Now,
We have to divide both of these sides of the equation by the number 2,
Then, we get,
= 2q/2 = - 6/2
= q = - 3
(l) 2q + 6 = 12
Ans:
First, we have to subtract the number 6 to the both sides of the following equation,
Then, we get,
= 2q + 6 - 6 = 12 - 6
= 2q = 6
Now,
We have to divide both of these sides of the equation by 2,
Then, we get,
= 2q/2 = 6/2
= q = 3
Q2: Solve the following equations:
(a) 2(x + 4) = 12
Ans:
Let us divide both these sides by 2,
= (2(x + 4))/2 = 12/2
= x + 4 = 6
By transposing four from the LHS to RHS, it becomes -4
= x = 6 - 4
= x = 2
(b) 3(n - 5) = 21
Ans:
Let us divide both these sides by 3,
= (3(n - 5))/3 = 21/3
= n - 5 = 7
By transposing -5 from the LHS to the RHS, it becomes 5
= n = 7 + 5
= n = 12
(c) 3(n - 5) = - 21
Ans:
Let us divide both these sides by 3,
= (3(n - 5))/3 = - 21/3
= n - 5 = -7
By transposing -5 from the LHS to the RHS, it becomes 5
= n = - 7 + 5
= n = - 2
(d) - 4(2 + x) = 8
Ans:
Let us divide both these sides by -4,
= (-4(2 + x))/ (-4) = 8/ (-4)
= 2 + x = -2
By transposing two from the LHS to the RHS, it becomes - 2
= x = -2 - 2
= x = - 4
(e) 4(2 - x) = 8
Ans:
Let us divide both these sides by 4,
= (4(2 - x))/ 4 = 8/ 4
= 2 - x = 2
By transposing the number 2 from the LHS to the RHS, it becomes - 2
= - x = 2 - 2
= - x = 0
= x = 0
Q3: (a) Construct 3 equations starting with x = 2
Ans:
First equation is,
Multiply both these side by 6
= 6x = 12 ... [equation 1]
Second equation is,
Subtracting the number 4 from both side,
= 6x - 4 = 12 -4
= 6x - 4 = 8 ... [equation 2]
Third equation is,
Divide both these sides by 6
= (6x/6) - (4/6) = (8/6)
= x - (4/6) = (8/6) ... [equation 3]
(b) Construct three equations that start with x = - 2
Ans:
First equation is,
Multiply both these side by 5
= 5x = -10 ... [equation 1]
Second equation is,
Subtracting the number 3 from both side,
= 5x - 3 = - 10 - 3
= 5x - 3 = - 13 ... [equation 2]
Third equation is,
Dividing both these side by 2
= (5x/2) - (3/2) = (-13/2) ... [equation 3]
Q4: Solve the following equations:
(a) 2y + (5/2) = (37/2)
Ans:
By transposing the fraction (5/2) from LHS to RHS, so it becomes -5/2
Then,
= 2y = (37/2) - (5/2)
= 2y = (37-5)/2
= 2y = 32/2
Now,
Divide both the side by the number 2,
= 2y/2 = (32/2)/2
= y = (32/2) × (1/2)
= y = 32/4
= y = 8
(b) 5t + 28 = 10
Answer :
By transposing 28 from the LHS to RHS, it becomes -28
Then,
= 5t = 10 - 28
= 5t = - 18
Now,
Dividing both these sides by 5,
= 5t/5= -18/5
= t = -18/5
(c) (a/5) + 3 = 2
Ans:
By transposing three from the LHS to RHS, it becomes -3
Then,
= a/5 = 2 - 3
= a/5 = - 1
Now,
Multiply both these sides by 5,
= (a/5) × 5= -1 × 5
= a = -5
(d) (q/4) + 7 = 5
Ans:
By transposing the number 7 from the LHS to RHS, it becomes -7
Then,
= q/4 = 5 - 7
= q/4 = - 2
Now,
Multiply both these sides by 4,
= (q/4) × 4= -2 × 4
= a = -8
(e) (5/2) x = -5
Ans:
First, we have to multiply both these sides by 2,
= (5x/2) × 2 = - 5 × 2
= 5x = - 10
Now,
We have to divide both these sides by 5,
Then we get,
= 5x/5 = -10/5
= x = -2
(f) (5/2) x = 25/4
Ans:
First, we have to multiply both these sides by 2,
= (5x/2) × 2 = (25/4) × 2
= 5x = (25/2)
Now,
We have to divide both these sides by 5,
Then we get,
= 5x/5 = (25/2)/5
= x = (25/2) × (1/5)
= x = (5/2)
Q5: Solve the following equations:
(a) 4 = 5(p - 2)
Ans:
Let us divide both these sides by 5,
= 4/5 = (5(p - 2))/5
= 4/5 = p -2
By transposing - 2 from the RHS to the LHS, it becomes 2
= (4/5) + 2 = p
= (4 + 10)/ 5 = p
= p = 14/5
(b) - 4 = 5(p - 2)
Ans:
Let us divide both these sides by 5,
= - 4/5 = (5(p - 2))/5
= - 4/5 = p -2
Now by transposing - 2 from the RHS to the LHS, it becomes 2
= - (4/5) + 2 = p
= (- 4 + 10)/ 5 = p
= p = 6/5
(c) 16 = 4 + 3(t + 2)
Ans:
By transposing four from the RHS to the LHS, it becomes - 4
= 16 - 4 = 3(t + 2)
= 12 = 3(t + 2)
Let us divide both these side by 3,
= 12/3 = (3(t + 2))/ 3
= 4 = t + 2
By transposing 2 from the RHS to the LHS it becomes - 2
= 4 - 2 = t
= t = 2
(d) 4 + 5(p - 1) =34
Ans:
By transposing 4 from the LHS to the RHS it becomes - 4
= 5(p - 1) = 34 - 4
= 5(p - 1) = 30
Let us divide both these side by 5,
= (5(p - 1))/ 5 = 30/5
= p - 1 = 6
By transposing - 1 from the RHS to the LHS it becomes 1
= p = 6 + 1
= p = 7
(e) 0 = 16 + 4(m - 6)
Ans:
By transposing 16 from the RHS to the LHS it becomes - 16
= 0 - 16 = 4(m - 6)
= - 16 = 4(m - 6)
Let us divide both these side by the number 4
= - 16/4 = (4(m - 6))/ 4
= - 4 = m - 6
Now by transposing - 6 from the RHS to the LHS it becomes 6
= - 4 + 6 = m
= m = 2
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