Let the side of one square be x. Area = x*x = x²
Then the side of other square would be 2x , Area = 2x*2x = 4x²
Combined area = x² + 4x² = 5x²
This combined area = 45 cm²
Therefore 5x² = 45 Divide both sides by 5
x² = 45/5
x² = 9 Take square root of both sides
x = √9
x = 3
Length of larger square is 2x = 2*3 = 6 cm
Length of larger square = 6cm
My favorite strategy is the criss cross method.

Take the numerator of the first fraction (2), and the denominator of the second fraction (8) and multiply them. The value 16 is now up on the left side, imaginary. (ALWAYS PUT THE PRODUCT ON THE SIDE WITH THE NUMERATOR) Now multiply the other diagonal. 3(7)=21. The 21 is on the right side. Now do 16 ? 21
Is it <, >, or =? The answer is <
I think this could be right
Solve for b:
5 a (b - c) = d
Divide both sides by 5 a:
b - c = d/(5 a)
Add c to both sides:
Answer: b = c + d/(5 a)