The system:
y = 3 x - 7
15 x - 5 y = 14
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Using the substitution method:
15 x - 5 · ( 3 x - 7 ) = 14
15 x - 15 x + 35 = 14
0 · x = 14 - 35
0 · x = - 21
x , y ∈ ∅
Answer:
D ) There is no solution.
A^2 + b^2 = c^2
9^2 + 12^2 = 225
square root of 225 is 15
15x + 2 = 45x + 4
Subtract 2 from both sides, as well as subtracting 45x from both sides.
15x - 45x = 4 - 2
-30x = 2
Divide both sides by -30.
x = 2/-30
x = - 1/15
~Hope I helped!~
Answer: 115 is the answer
Step-by-step explanation:
First set up your two equations:
x + y = 90
x = 2y - 30
Then substitute what x equals in the second equation into the first equation:
(2y -30) + y = 90
Now solve for y:
3y -30 = 90
3y = 120
y = 40
Then use y = 40 and substitute the value for y into one of your original equations and solve for x. I'll choose the first one, but either one will work.
x+ 40 = 90
x = 50
So your solution is x = 50 and y = 40
