Answer:
1.a=2
2. C x=2 and x=-3
Step-by-step explanation:
The standard form for the quadratic function is
ax^2 +bx+c
so we need to rewrite the function to be in this form
2x^2 -10 = 7x
Subtract 7x from each side
2x^2 -7x-10 = 7x-7x
2x^2 -7x-10 = 0
a =2, b= -7 c=-10
2. The quadratic formula is
-b ± sqrt(b^2 -4ac)
----------------------------
2a
2x^2 + 2x=12
Lest get the equation in proper form
2x^2 + 2x-12 = 12-12
2x^2 +2x-12 =0
a=2 b=2 c=-12
Lets substitute what we know
-2 ± sqrt(2^2 -4(2)(-12))
----------------------------
2(2)
-2 ± sqrt(4+96)
----------------------------
2(2)
-2 ± sqrt(100)
----------------------------
4
-2 ± 10
----------------------------
4
-2 + 10 -2-10
----------- and --------------
4 4
8/4 and -12/4
2 and -3
Answer:
Allison worked 6 hours lifeguarding and 3 hours washing cars.
Step-by-step explanation:
Let
Number of hours Allison worked lifeguarding last week = x
Number of hours Allison worked washing cars last week = y
1. Last week Allison worked 3 more hours lifeguarding than hours washing cars hours, then

<u>Lifeguarding:</u>
$12 per hour
$12x in x hours.
<u>Washing cars:</u>
$8 pere hour
$8y in y hours.
2. Allison earned a total of $96, hence

You get the system of two equations:

Plot the graphs of these two equations (see attached diagram). These line intersect at point (6,3), so Allison worked 6 hours lifeguarding and 3 hours washing cars.
Add the ratio to get total shares: 4 +1 = 5
Divide the total amount to share by the total shares:
150 / 5 = 30
Now multiply each set of shares by that:
4 x 30 = 120
1 x 30 = 30
120-30 = 90 more
Answer:
3 packs equal the price of two, therefore 1.43•2= 2.86
and 6 packs equal the price of 4, so 2.86•2= 5.72
Answer:

Step-by-step explanation:

Subtract 15 from both sides of the equation.

