Answers>Maths>GCSE>Article

You are told that y is proportional to x^2 and that y=75, x=5. Find a formula for y in terms of x.

You know that y is proportional to x², so let y=kx² . You also know that y=75 and x=5. Substitute y=75 and x=5 into the equation y=kx² . Therefore: 75=k multiplied by 5². 75=25k. 75/25=k. k=3. Put k back into the original equation y=kx². y=3x².

Answered by Anna G. • Maths tutor

3769 Views

See similar Maths GCSE tutors

You are told that y is proportional to x^2 and that y=75, x=5. Find a formula for y in terms of x.

Related Maths GCSE answers

A square based pyramid with corners ABCD has side length 6 cm. The distance from the centre of the square (C) to the top vertex of the pyramid (V) is 4 cm. Work out the total surface area of the pyramid.

How do I divide fractions?

Expand and simplify 3 (y + 4) - 2 (4y + 1)

Solve x^2+7x+12=0