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4 votes
Determine the solution to the system of equations by using substitution.

Y=4x+10
Y=-5x-10

2 Answers

1 vote

y=4x+10\\ y=-5x-10\\\\ 4x+10=-5x-10\\ 9x=-20\\ x=-(20)/(9)\\\\ y=4\cdot(-(20)/(9))+10\\ y=-(80)/(9)+(90)/(9)\\ y=(10)/(9)\\
User Alex McGill
by
8.2k points
4 votes
Steps:
1. Substitute the y in 4x + 10 with -5x-10
-5x-10= 4x + 10
2. Add 5x on both sides
-10= 9x + 10
3. Subtract 10 on both sides
-20= 9x
4. Divide by 9 on both sides
5. Your answer is
X= -20/9
User Mitja Gustin
by
8.2k points