W=l-8
a=9
a=lw
9=(l-8)l
9=l²-8l
0=l²-8l-9
factor
0=(l-9)(l+1)
set to zero
l-9=0
l=9
l+1=0
l=-1, false length can't be negative
l=9
the length is 9 units long
Answer:
40
Step-by-step explanation:
To solve this, we can create an equation that represents this situation. Since Christopher score 7 more than twice what Mathew scored, the equation will be:
C = 2M + 7
(Variables are representative of the first letter of each name)
Seeing as Christopher scored 87, we can put that into the equation and solve for M.
So, the equation will be:
87 = 2M + 7
Subtract 7 from both sides in order to isolate variable M on the right side.
80 = 2M
Now solve for M, which is 40 (divide both sides by 2).
Answer: Yes, 
<u>Step-by-step explanation:</u>
f(x) = 3x - 6 is a line so it is a function because
it passes the vertical line test
and the horizontal line test
To find the inverse, swap the x's and y's and solve for y

Answer:
Step-by-step explanation:
A dime is worth 10 cents. Converting to dollars, it becomes 10/100 = $0.1
A quarter is worth 25 cents. Converting to dollars, it becomes 25/100 = $0.25
Let x represent the number of dimes that Jayden has.
Let y represent the number of quarters that Jayden has.
Jayden has some dimes and some quarters. He has at most 25 coins. It means that
x + y ≤ 25
The coins worth at least $4.60 combined. It means that
0.1x + 0.25y ≥ 4.6 - - - - - - - - - - 1
If Jayden has 7 dimes, then
7 + y ≤ 25
y ≤ 25 - 7
y ≤ 18
Substituting x = 7 into equation 1, it becomes
0.1 × 7 + 0.25y ≥ 4.6
0.7 + 0.25y ≥ 4.6
0.25y ≥ 4.6 - 0.7
0.25y ≥ 3.9
y ≥ 3.9/0.25
y ≥ 15.6
All possible values for the number of quarters that he could have would be
15.6 ≤ y ≤ 18