Answer:
Each car used 7 quarts of oil. So 7 cars would use 7×17 quarts which would be 119 quarts.
Answer:
R290.1
Step-by-step explanation:
Let
x = charge before he put his prices up
New charge = R320
Percentage increase in price = 7%
x + 7% of x = 320
x + 0.07 * x = 320
x + 0.07x = 320
1.07x = 320
x = 320/1.07
x = 299.06542056074
Approximately
x = R290.1
Charge before he put his prices up = R290.1
You could complete the square to state the vertex.
You could use the quadratic equation to find the roots (which are complex).
Try an example that will require both.
y = x^2 + 2x + 5
Step One
Get the graph. That's included below.
Step Two
Provide the steps for completing the square.
Note: we should get (-1,4)
y= (x^2 +2x ) + 5
y = (x^2 +2x + 1) + 5 - 1
y = (x +1)^2 + 4
The vertex is at (-1,4)
Step Three
Find the roots. Use the quadratic equation. Note that the graph shows us that the equation never crosses or touches the x axis. The roots are complex.

a = 1
b = 2
c = 5




x = -1 +/- 2i
x1 = -1 + 2i
x2 = -1 - 2i And we are done.