Test: Squares and Square Roots - Class 8 MCQ

The square root of 0.04 is 0.2 because 0.2 × 0.2 = 0.04. This illustrates how square roots can also be applied to decimal numbers.

The equation x² = 49 has two solutions: x = 7 or x = -7. This is important in algebra as it illustrates the concept of positive and negative roots.

The pair 2 and 2 will yield 4, which is a perfect square because 2 × 2 = 4. Recognizing pairs that form perfect squares is useful in number theory.

A perfect square is a number that has an integer as its square root. 25 is a perfect square because 5 × 5 = 25. In contrast, 20, 30, and 50 do not have integer square roots.

The square root of 50 is approximately 7.07, which rounds to 7. This demonstrates how to estimate square roots of non-perfect squares.

The squares of 4 (which is 16), 6 (which is 36), and 14 (which is 196) all end with the digit 6. This is part of the properties of square numbers.

The square of an odd number is indeed always odd. For example, 3² = 9 and 5² = 25. On the other hand, the squares of even numbers are always even, and the square of zero is zero, which is not negative.

To determine if a number is a perfect square, you can factor it into primes and check if all prime factors can be paired. For instance, 36 = 2² × 3² is a perfect square because all primes are paired.

The square of a decimal number has double the number of decimal places compared to the original. For example, squaring 0.1 results in 0.01, which has 2 decimal places.

A number with n zeros at the end will have 2n zeros when squared. Therefore, if a number has 3 zeros, its square will have 2 × 3 = 6 zeros.

The square root of a number is the value that, when multiplied by itself, gives the original number. Here, 8 × 8 = 64, so the square root of 64 is 8. This understanding is crucial for simplifying expressions in algebra.

The statement that the square of an odd number is even is false. Odd numbers squared remain odd. For example, 3² = 9, which is odd.

The square root of 1.44 is 1.2 since 1.2 × 1.2 = 1.44. This shows how square roots can be calculated for decimal values as well.

The square of 0.5 is 0.25 because 0.5 × 0.5 = 0.25. This shows how squaring decimal values works similarly to whole numbers.

The square of a negative number is always positive because multiplying two negative numbers results in a positive number. For example, (-5) × (-5) = 25.