To find the value of y that makes the equation true, (7y)^2 = 49^2:
(7y)^2 = 49^2
49y^2 = 2401
Dividing both sides by 49:
y^2 = 2401 / 49
y^2 = 49
Taking the square root of both sides:
y = √49
There are two solutions for y, which are y = 7 and y = -7, because both 7^2 and (-7)^2 equal 49.