Question

Solve using elimination:-3y = -9x − 3
-12x + 4y = 4 (-2, 7)
Infinitely many solutions No solution (-4, 13)

Answer 1

-3y = -9x − 3
-12x + 4y = 4

Answer 2

lets change this equation...
-3y = -9x - 3 =
9x - 3y = -3
thats better....now we have
9x - 3y = -3 -->(4)
-12x + 4y = 4 -->(3)
-----------------
36x - 12y = -12 (result of multiplying by 4)
-36x + 12y = 12 (result of multiplying by 3)
----------------add
0 + 0 = 0
0 = 0

when the system ends with them equaling, that means there are INFINITELY MANY SOLUTIONS

Answer 3

help me with this one please

Solve using substitution:
-5x − y + 15 = 0
4x = -10 − 3y
(1, 10)
(2, 5)
(3, 0)
(5, -10)
.

Answer 4

we are going to isolate y in the first equation
-y = 5x - 15 (now I will multiply it by -1 to make y positive.
resulting in : y = -5x + 15
Now we will sub -5x + 15 in for y in the 2nd equation.
4x = -10 - 3y
4x = -10 - 3(-5x + 15)
4x = -10 + 15x - 45
4x - 15x = -55
-11x = -55
x = 5

now sub 5 in for x in either of the original equations to find y
y = -5x + 15
y = -5(5) + 15
y = -25 + 15
y = -10

answer is (5,-10)

any questions ?

Answer 5

yes i have more lol

Answer 6

Select the choice below that could be the first step in solving the following system of equations using elimination:
-7x + 5y = -12
8y − 3x + 3 = 0
Write the second equation in terms of x.
Replace the right side of the first equation with the second equation.
Multiply the second equation by -7.
Multiply the first equation by -5.

Answer 7

@Gabriella77