Let a = 4b + 5(c - b). Find the value of c when a = 8 and b = 7.

a = 4b + 5(c - b) - question8 = (4*7) + 5(c - 7) - insert values given in question8 = 28 + 5c -35 - multiply and expand brackets8 - 28 + 35 = 5c - take away 28 from the left and right-hand side of the equation. Add 35 to the left and right-hand side also15 = 5c - simplify15/5 = c - divide right hand side by constant on left hand side so the variable c is on its own3 = c - answer

GH

Related Maths GCSE answers

All answers ▸

What's the quadratic formula used for?


There are n sweets in a bag. 6 are Orange, the rest are Yellow. Hannah takes a sweet out of the bag, and eats it, she does this twice. The Probability of Hannah eating two orange sweets is 1/3. Show that n^2 - n - 90 =0, and solve to find the value of n.


Samuel had 3 piles of coins, I, II and III. Altogether there was 72p. Pile II had twice as much as pile I. Pile III had three times as much as pile II. How much money was in Pile III?


How to find the gradient of a line?