Answer:
-20x.....
Step-by-step explanation:
–4(5x)
-20x
The second equation equals: 3X +18y=60 (Both sides times 3)
And then use this new equation minus the first equation, you will get:
Left side: (3X +18y) - (<span>3x+6y)
Right side: 60-30
So 12y=30
Then y=2.5
Take y value into one of the three equations, you will get x=5
or
in another easier way:
Directly minus the second equation from the first one:
</span>(3x+6y) -(<span>X+6y)=10
</span>2X = 10
X = 5
Get Y is easy, Y=2.5
28=(2+x)+x
-2 -2
_________
26=x+x
26=2x
Divide both by 2
13=x
length=15 width=13
Answer:
A)3.74
B)17.04
C)61.92
Step-by-step explanation:
The equation of the line of best fit:

Where x is time in hours
y = midterm score
a)For an increase of one hour in the time spent studying, what is the predicted increase in the midterm score?
General equation y = mx+c
where m is the slope .
On comparing m = 3.74
Slope is the rate of increase per hour
So, For an increase of one hour in the time spent studying, the predicted increase in the midterm score is 3.74
b)What is the predicted midterm score for a student who doesn't spend any time studying?
Substitute x = 0
y=3.74x+17.04
y=3.74(0)+17.04
y=17.04
c)What is the predicted midterm score for a student who studies for 12 hours?
Substitute x = 12
So,y=3.74x+17.04
y=3.74(12)+17.04
y=61.92