81- answer is ok but im not suree
99*(4/3)=x
99*1.333=x
x=132
This week's movie was 132 minutes long, or 2 hours 12 minutes long.
First thing to do is to move the constant over to the other side of the equals sign. Then we will complete the square on the x terms. We will take half the linear term, square it, then add it to both sides. Our linear term is 4. Half of 4 is 2, and 2 squared is 4.
. In the process of completing the square we have created a perfect square binomial on the left which is
. A is our answer.
Answer:
20
Step-by-step explanation:
The first equation is 50 - 2x (because you start with $50 and subtract 2 for each 30 day period)
The second equation is 40-1.5x
Set them equal to each other: 50 - 2x = 40 - 1.5x
Solve for x:
50 - 2x = 40 - 1.5 x
+2x +2x
-----------------------
50 = 40 + 0.5 x
-40 -40
-------------------
10 = 0.5 x
20 = x
So there will be 20 30-day periods until the cards will be equal in value.
Check: After 20 periods, 50 - 2(20) = $10 left
40 - 1.5(20) = also $10 left
Just find the vertex and then compare with graph
#a
Parabola opening upwards
Graph 3
#2
Vertex at (-3,0)
Graph IV
#3
Parabola opening downwards as a is -ve
Graph I
#4
One graph is left
