Given that G is directly proportional to the square of H. If G is 5 when H is 3, find H when G is 100.

Answer 1

You can set this up with an equation and use cross multiplication.

5/3² = 100/x²

Using order of operations you need to square the H value before cross multiplying.

5/9 = 100/x²

900 = 5x²

180 = x²

x = √180

Depending on your teacher you can use a calculator or simplify.

x = √(20 · 9)

x = 3√20

x = 3√(5 · 4)

x = 3·2·√5

x = 6√5