If you transform x 2 + y 2 = 25 into 4x 2 + 4y 2 = 25, which option below describes the effect of this transformation on the radius? a. it divides the radius by 4. b. it multiplies the radius by 4. c. it divides the radius by 2. d. it multiplies the radius by 2.

Answer

c. It divides the radius by 2.

Explanation

The general equation of a circle is

(x-h)² + (y-k)² = r²

Where (h, k) makes the coordinates of the circle and r the radius.

x² + y² = 25 For this equation,

center (0, 0)

Radius = √25 = 5

4x² + 4y² = 25 First simplify this equation

4x² + 4y² = 25 ⇒ x² + y² = 25/4

center (0, 0)

Radius = √(25/4) = 5/2

The radius has been divided by 2

15

step-by-step explanation:

we are given the following expression and we are to solve it and find the product:

-13 × (-5)

solving the given expression in the standard order of solving a mathematical expression, beginning with the opening of brackets and then multiplying the terms and changing their signs.

-3 × -5 = 15 (answer is positive because when negative is multiplied with negative, it gives a positive answer)