How do I solve simultaneous equations using the substitution method?

2y + x = 8 (equation 1) and 1 + y = 2x (equation 2)Step 1: make y subject of equation 2: y = 2x - 1 Step 2: sub this value of y into equation 1: 2(2x - 1) + x = 8 Step 3: solve the above equation to find x: 4x -2 + x = 8 --> 5x = 10 --> x = 2 Step 4: sub this value of x into either equation 1: 1 + y = 2(2) --> y = 4 - 1 --> y = 3 Answer: x = 2 and y = 3

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Answered by Lulu H. Maths tutor

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