How do you solve these two equations with the substitution method: 7x + 4y = 5 and x - 6y = -19?

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jumpman jumpman
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How do you solve these two equations with the substitution method: 7x + 4y = 5 and x - 6y = -19?

AlgebraHouse AlgebraHouse
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Re: How do you solve these two equations with the substitution method: 7x + 4y = 5 and x - 6y = -19?

7x + 4y = 5
x - 6y = -19---> x = 6y - 19 {added 6y to both sides}

7x + 4y = 5 {top equation}
7(6y - 19) + 4y = 5 {substituted 6y - 19, in for x, into top equation}
42y - 133 + 4y = 5 {used distributive property}
46y - 133 = 5 {combined like terms}
46y = 138 {added 133 to both sides}
y = 3 {divided both sides by 46}

x = 6y - 19
x = 6(3) - 19 {substituted 3, in for y, into 6y - 19}
x = 18 - 19 {multiplied 6 by 3}
x = -1 {subtracted 18 - 19}

x = -1 and y = 3