Test: Simplifying expressions - Year 7 MCQ

If you have x rabbits and I have twice as many, the number of rabbits I have can be expressed as: 
2x (which is two times the amount of x)
Therefore, the correct answer is 2x

To find out how old Rosie's mother is now, we can follow these steps:

Let Suzie's age be x.

Rosie is four years older than Suzie, so Rosie's age is x + 4.

Rosie's mother was 28 years old when Rosie was born.

This means that Rosie's mother is now (x + 4) + 28 years old.

Simplifying this gives: x + 32.

Thus, Rosie's mother's current age is x + 32.

If Peter has x brothers, Peter is not included in that count (same for Paul & Graham). But since they are siblings, the numbers might overlap. If x, y, z refer to the same set of brothers, total isn’t just x + y + z.
However, since this is a basic algebra practice question, adding them is acceptable.

In an algebraic expression, letters are used to represent values. These values can be numbers that vary, allowing us to express different mathematical relationships. The use of letters makes it easier to work with unknown quantities and to formulate equations that describe various situations.

Combine like terms: 3x + 4x − 2x = (3 + 4 − 2) x = 5x.

Subtract 5 from both sides: 4x = 12. Divide both sides by 4: x = 3.

Substituter = 3 into the formula: A = π⋅3 2 = 9π.

To simplify the expression 3a + 4b + 6c + 3a - 6c - a - 3b, follow these steps:

• First, combine like terms for a: 3a + 3a - a equals 5a.
• Next, combine the terms for b: 4b - 3b equals b.
• Now, for c: 6c - 6c cancels out to 0.

This gives you the simplified expression: 5a + b.

To simplify the expression 7m + 2n - 3m + 4n, follow these steps:

• Combine the m terms: 7m - 3m = 4m.
• Combine the n terms: 2n + 4n = 6n.

Putting it all together, the simplified expression is: 4m + 6n.

To simplify the expression 4a + 5a - 2a, follow these steps:

• 4a + 5a = 9a
• Then, subtract 2a: 9a - 2a = 7a.

The simplified expression is 7a.