SOLUTION: Solve this question using substitution y=5x+5 y=15x-1

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Question 566566: Solve this question using substitution y=5x+5 y=15x-1
Answer by Maths68(1474) About Me  (Show Source):
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y=5x%2B5........(1)
y=15x-1.......(2)
Substitute the value of y from (2) to (1)
15x-1=5x%2B5
15x-5x=5%2B1
10x=6
10x%2F10=6%2F10
cross%2810%29x%2Fcross%2810%29=cross%286%29%2Fcross%2810%29
x=3%2F5
Put the value of x in (1)
y=5x%2B5........(1)
y=5%283%2F5%29%2B5
y=cross%285%29%283%2Fcross%285%29%29%2B5
y=3%2B5
y=8

x,y = 3/5, 8

Check
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Put the value of x and y in (1)
y=5x%2B5........(1)
8=5%283%2F5%29%2B5
8=5%283%2F5%29%2B5
8=cross%285%29%283%2Fcross%285%29%29%2B5
8=3%2B5
8=8
Put the value of x and y in (2)
y=15x-1
8=15%283%2F5%29-1
8=cross%2815%29%283%2Fcross%285%29%29-1
8=%283%29%283%29-1
8=9-1
8=8