1. This must be greater than or equal to 0 (there can't be any negatives!)
8 - .5t ≥ 0.
8 ≥ .5t
t ≤ 16
D.
2. 4(2x-1) = 2x + 35
8x - 4 = 2x + 35
6x = 39
x = 6.5
H.
3. c = .8(x-15) = .8x-12
A.
4. m = number of marble cupcakes
s = number of strawberry shortcake cupcakes
6m + 8.5s = 391
m = 1/2s
6(.5s)+8.5s = 391
11.5s = 391
s = 34
m = 17
F.
5. B
6. Use substitution
2x + 3x = 10
5x = 10
x = 2
7. (sorry I'm not sure!)
8. G
9. L = number of balls
B = number of bats
L + B = 100
B = 100 - L
4.5L+20B = 822
4.5L + 20(100-L) = 822
4.5L -20L + 2000 = 822
1178 = 15.5L
L = 76
10. J
Step-by-step explanation:

Hope it will help :)
Answer:
-5/3
Step-by-step explanation: rise over run it goes down -5 and goes across 3
Answer/Step-by-step explanation:
a. Using two points on the line (0, 2) and (4, 12), find the gradient:
Gradient = ∆y/∆x = (12 - 2) / (4 - 0) = 10/4 = 2.5
Gradient = 2.5
b. The gradient, 2.5, represents the unit rate. That is, the volume of the oil in the tank per second.
i.e. 2.5 litres per second
c. The value, L = 2 represents the y-intercept, which is the starting value or initial volume of oil in the tank at 0 secs.
Answer:
x > 0, if not 4/x < 0
0 < 4/x < 6/7
0 < 28/x < 6
0 < 28 < 6x
0 < 4 2/3 < x
Step-by-step explanation: