SOLUTION: I am confused on how to do these kind of problems. The same with chapter 3 Section 3 I am not sure how to solve using substitution and eliminations

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Question 60148This question is from textbook Intermediate Algebra
: I am confused on how to do these kind of problems. The same with chapter 3 Section 3 I am not sure how to solve using substitution and eliminations This question is from textbook Intermediate Algebra

Answer by checkley71(8403) (Show Source):
You can put this solution on YOUR website!
X+7Y=10
-6X+8Y=-10
USING THE SUBSTITUTION METHOD SOLVE ONE OF THE EQUATIONS FOR X OR Y
X=10-7Y NOW SUBSTITUTE (10-7Y) FOR X IN THE OTHER EQUATION
-6(10-7Y)+8Y=-10
-60+42Y+8Y=-10
50Y=60=10
50Y=50
Y=50/50
Y=1 NOW SUBSTITUTE 1 FOR Y IN EQUATION 1 WE GET
X+7*1=10
X+7=10
X=10-7
X=3
NOW FOR THE ELIMINATION METHOD USING THE SAME EQUATIONS
X+7Y=10
-6X+8Y=-10 NOW WE MULTIPLY EQUATION 1 BY 6 WE GET
6X+42Y=60 NOW ADD THESE TWO EQUATIONS
----------------------
0X+50Y=50
50Y=50
Y=50/50
Y=1 NOW SUBSTITUTE I FOR Y IN EITHER EQUATION WE GET
-6X+8*1=-10
-6X+8=-10
-6X=-10-8
-6X=-18
X=-18/-6
X=3
HOPE THIS HELPS :)