im a senior in high school and doing credit recovery and need help with math a lot.
Solve using substitution: -y - 5x = -7 2y - 2x = 14
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First, solve one of the equations for one of the expressions:
-y -5x = -7
-y = 5x - 7
y = -5x + 7
Then, substitue this for y in the other equation:
2(-5x + 7) -2x = 14
-10x +14 - 2x = 14
-12x +14 = 14
-12x = 0
x = 0
Then, solve the other equation by substituting this value for x.
y = -5x + 7
y = -5(0) +7
y = 0 + 7
y = 7
Now check your work:
-y-5x=-7 Solve where x=0 and y=7
-7 -5(0) = -7
-7 = -7
2y-2x=14 Solve where x=0 and y=7
2(7) -2(0) = 14
Lets label the two equations as A) and B):
First, we can solve equation A) for y, as follows:
Add 5x to both sides: -y=-7+5X
Multiply both sides by -1: y=7-5x
Next we can substitute this result for y into equation B), simplify, and solve for x as follows:
x=0 We have now solved for x.
Finally, we can plug 0 in for the value of x in either equation, to solve for y. Let's use equation A):
y=7 We have now solved for y.
We can check this result by substituting the values for x and y (0 and 7) back into each equation A) and B) to ensure that the values work. This can be left to the student.
Hope this helps!