Search over 10,000 free study notes

This is a simultaneous equation problem.If 4x = 9y then 2x = 4.5y.Then by substitution, 4.5y + 5y = 95.Then 9.5y = 95 (divide by 9.5) gives y = 10.By using back substitution 2x = 4.5*10 = 45 (divide by 2 ...

The gradients of the two lines must be the same. The gradient is m in the equation: y=mx+c For example: L1: y = 3x – 2L2: 3y – 9x + 5 = 0 First rearrange L2 so it is in the same form as L1 to get:3y=9x-5T...

First step is to understand what it means for lines to be parallel. This is when the gradients of two lines are the same.This is much easier to see when the format of the equations is the same, so lets re...

Find 90% of 130Calculate the value of 10%130 / 10 = 13You can now use this value to find the answer as 100% - 10% = 90%130 - 13 = 117

Firstly we need to set up a simultaneous equation. 3t +2c =7.80 and 5t +4t = 14.20 Rearrange the first equation to find c on its own. 2c = 7.80 - 3t, c= (7.80 - 3t) / 2Then put the new value of c into the...