Answer:
x = 0
y = 4
Step-by-step explanation:
Given
12x - 5y = -20
y = x + 4
Substitute x + 4 for y in the first equation
12x - 5(x + 4) = -20
Expand the bracket
12x -5 X x - 5 x 4 = -20
12x - 5x - 20 = -20
7x - 20 = -20
Add 20 to both sides to eliminate -20 on the left side
7x - 20 + 20 = -20 + 20
7x = 0
Divide both sides by 7 to isolate x
7x/7 = 0/7
x = 0
Substitute 0 for x in either equation to get y
Using equation 2, we have
y = x + 4
= 0 + 4
= 4
x = 0
y = 4
Answer:
c
Step-by-step explanation:
There is no difference, 6rs-(-2rs) if you get rid of the parenthesis you are left with 6rs- -2rs and two negatives make a positive therefore the answer will become 8rs... I hope this helps :)
Answer:
20 minutes
Step-by-step explanation:
The mean, or average of a data set can be found by adding all the values together, and dividing by the number of values.
The data set is: 20 minutes, 22 minutes and 18 minutes
1. Add the values together
Add all the numbers in the set together.
Data set: 20, 22, 18
Add them: 20+22+18
60
2. Divide by the number of values
Count how many numbers are in the set.
In this set, there are 3 numbers.
Divide 60 by 3
60/3 =20
20 minutes
His mean time is 20 minutes.
