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Use the substitution method to solve the system of equations. y=7x +8 y=x +20​

User Thoean
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1 Answer

3 votes

Answer:

x = 2, y = 22 → (2, 22)

Explanation:


\left\{\begin{array}{ccc}y=7x+8&(1)\\y=x+20&(2)\end{array}\right\qquad\text{substitute (1) to (2):}\\\\7x+8=x+20\qquad\text{subtract 8 from both sides}\\7x=x+12\qquad\text{subtract x from both sides}\\6x=12\qquad\text{divide both sides by 6}\\x=2\\\\\text{put the value of x to (2):}\\\\y=2+22\\y=22

User Patrick Allwood
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