Answer:
D. Divide both sides by - 8
Step-by-step explanation:
-8x = 312
x = 312/(-8)
x = - 39
He payed 0.72
First you take 2.88, then you multiply it by 1/4 or a simpler way would be to divide 2.88 by 4. The answer is $0.72
Commutative law: a+b=b+a thats it...
So 9+7 can also be written as 7+9=16
Answer:
a constant is a data item whose value cannot change during the program execution just as its name implies that the value is constant a variable is a data item whose value can change during the program's execution . Thus as its name implies the the value can vary
It looks like your equations are
7M - 2t = -30
5t - 12M = 115
<u>Solving by substitution</u>
Solve either equation for one variable. For example,
7M - 2t = -30 ⇒ t = (7M + 30)/2
Substitute this into the other equation and solve for M.
5 × (7M + 30)/2 - 12M = 115
5 (7M + 30) - 24M = 230
35M + 150 - 24M = 230
11M = 80
M = 80/11
Now solve for t.
t = (7 × (80/11) + 30)/2
t = (560/11 + 30)/2
t = (890/11)/2
t = 445/11
<u>Solving by elimination</u>
Multiply both equations by an appropriate factor to make the coefficients of one of the variables sum to zero. For example,
7M - 2t = -30 ⇒ -10t + 35M = -150 … (multiply by 5)
5t - 12M = 115 ⇒ 10t - 24M = 230 … (multiply by 2)
Now combining the equations eliminates the t terms, and
(-10t + 35M) + (10t - 24M) = -150 + 230
11M = 80
M = 80/11
It follows that
7 × (80/11) - 2t = -30
560/11 - 2t = -30
2t = 890/11
t = 445/11