Answer:
Step-by-step explanation:
5x-4=20
5x=24: x=24/5
y=3x-12
y=3(24/5)-12
y = (72-60)/5
y=12/5
The answer will be (-2,-7)
Solve for y by setting one equation =to X after that you can substitute the equation into the other one let's set the first one in X= FORM
X-7y=10
-2x+14y=-20
Add 7y to both sides of the first equation to let x stand alone
X=7y+10
Now you can substitute x on the second equation
-2 (7y+10)+14y=-20
Distribute
-14y-20+14y=-20
Add and simplify
Us cancel out =0
-20=-20
0=0
They are the same equations you can also divide the second equation by -2 which would make it look like this
X-7y=10
-2 (x-7y=10)
Let me know if I have answered your question
Answer:
x = -12
Step-by-step explanation:
-2.5(x-4)=-3x+4
Distribute
-2.5x +10 = -3x +4
Add 3x to each side
-2.5x+10 +3x = -3x+4+3x
.5x +10 = 4
Subtract 10 from each side
.5x+10-10=4-10
.5x = -6
Divide by .5
.5x/.5 = -6/.5
x = -12
Answer:
Step-by-step explanation:
x = small barrettes
y = large barrettes
13x + 11y = 142.......multiply by -1
13x + 12y = 149
-----------------------
-13x - 11y = -142 (result of multiplying by -1)
13x + 12y = 149
------------------------add
y = 7..........large barrettes used 7 yards
13x + 11y = 142
13x + 11(7) = 142
13x + 77 = 142
13x = 142 - 77
13x = 65
x = 65/13
x = 5........small barrettes used 5 yards
