Answer:
Look at the equations:
y
=
−
9
x
−
21
and
y
=
5
x
+
7
Because both equations equal (y), they both equal the same.
If an equations says "
y
=
−
9
x
−
21
" , that means we can replace (y) with
−
9
x
−
21
.
Therefore when i take the equation:
y
=
5
x
+
7
, we can replace (y) to get:
−
9
x
−
21
=
5
x
+
7
Now isolate (x):
−
9
x
−
21
=
5
x
+
7
⇔
−
21
=
14
x
+
7
⇔
−
28
=
14
x
⇔
x
=
−
2
Answer:
Alison wins against Kevin by 0.93 s
Step-by-step explanation:
Alison covers the last 1/4 of the distance in 3 seconds, at a constant acceleration
, we have the following equation of motion

where s (m) is the total distance, ta = 3 s is the time


Similarly, Kevin overs the last 1/3 of the distance in 4 seconds, at a constant acceleration
, we have the following equation of motion:

tk = 4 s is the time


Since
we can conclude that
, so Alison would win.
The time it takes for Alison to cover the entire track



The time it takes for Kevin to cover the entire track



So Alison wins against Kevin by 6.93 - 6 = 0.93 s
The length is 7 and the width is 3
Answer:
n=15
Step-by-step explanation:
5(n+1)=2n+20
U start by expanding the first term which will give you 5n+5
Then after that u collect like terms giving u
5n-2n=20-5
Finally u evaluate it giving u
n=15
Answer:
v = 220 yd²
Step-by-step explanation:
Small portion
v = 5 * 4 * 3
v = 60 yd²
Large portion
v = 9 * 6 * 3
v = 162 yd²
Total
v = 60 + 162
v = 220 yd²