Answer: -4
Step-by-step explanation:
-1.5(4-r)=-12
Divide both sides by -1.5
4-r=8
-r=4
r=-4
Therefore, the value of r is -4
ANSWER
10 weeks, $310
EXPLANATION
We have a system of linear equations as both equations need to be satisfied by the same ordered pair (x,y):
y = 25x + 60
y = 30x + 10
We can solve this by substitution. Since y is equal to 25x+60, we can substitute in 25x + 60 for y in the equation y=30x+10
y = 30x + 10
25x + 60 = 30x + 10
Subtract 25x from both sides
60 = 5x + 10
Subtract 10 from both sides and then divide both sides by 5
50 = 5x
x = 10
x represents time in weeks, so 10 weeks.
Find y, the amount of money, by substituting x=10 into either equation.
If we use y = 30x + 10, then
y = 30x + 10
y = 30(10) + 10
y = 300 + 10
y = 310
y = 310 implies $310 so the answer is 10 weeks, $310.
9 is 18% of 50. So, 50 percent also written as 50% means 50 out of 100 parts. Since there are exactly two 50s in 100, fifty percent is the same number as one half. 50 percent=0.5 in but as a fraction, its 1/2.
