Solve the simultaneous equations: 2x + y = 5 , x + 4y = -22
Showing each step of working is important.First, we need to rearrange one of the equations to solve for x or y.If we rearrange the first equation to solve for y in terms of x we get: y = 5 - 2x ( by subtracting 2x from both sides)We can now substitute 5 - 2x in as y in the second equation, which gives us: x + 4(5 - 2x) = -22If we now expand these brackets we find: x + 20 - 8x = -22, this can be simplified to 7x + 20 = -22If we move the 20 to the other side of the brackets we get: -7x = -42Divide both sides by 7 to find x: x = 6We can then use this x value to find y in either equation.2(6) + y = 512+ y = 5y = -7So x = 6 , y = -7
JF
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