Answer:
x=6
Step-by-step explanation:
Step 1: Divide both sides by 17.
17x17=10217
x=6
Answer:
14. x=-2.5, y = -7
15. x=28 y = -20
Step-by-step explanation:
14. Let's solve this system by elimination. Multiply the first equation by -1.
-1*(4x-y)= -1*(- 3)
-4x +y = 3
Then add this to the second equation.
-4x+y = 3
6x-y= - 8
--------------
2x = -5
Divide each side by 2
x = -2.5
We still need to find y
-4x+y =3
-4(-2.5) + y =3
10 +y =3
Subtract 10 from each side.
y = 3-10
y = -7
15.I will again use elimination to solve this system, because using substitution will give me fractions which are harder to work with. I will elimiate the y variable. Multiply the first equation by 11
11(
5x+6y)= 11*20
55x+66y = 220
Multiply the second equation by -6
-6(9x+11y)=32*(-6)
-54x-66y = -192
Add the modified equations together.
55x+66y = 220
-54x-66y = -192
---------------------------
x = 28
We still need to solve for y
5x+6y = 20
5*28 + 6y =20
140 + 6y = 20
Subtract 140 from each side
6y = -120
Divide by 6
y = -20
Answer:
C & D
Step-by-step explanation:
You can do these two ways. You can multiply the cost of the the shirt by 15% (.15 as a decimal.) and then subtract that answer from the original price of the shirt to get the sales price of the shirt.
You can also multiply the price of the shirt by 85% (.85 as a decimal) and that will give you the sales price without having to subtract. 15% + 85% = 100%, so 85% represents the sales price of the shirt.
Anyway, since you multiply, you can eliminate choice A & B.
Since the direction in the question says to select all that apply, I would check both C & D.
C is the equation of the first way I talked about- Price - 15% * price
C p - 0.15p
D is the equation of the second way I talked about. Price times 85%
D 0.85p
