Answer:
Exercise 1 : a. 4 ; b. -4
Exercise 2 : a. +7 positive/right ; b. -7 ; c. -7 negative/left
Step-by-step explanation:
I can only guess that you meant to write
12 + 3 = 3 + 12
which would be the commutative property of addition.
Answer: In five months,she will save the same money which is $250.
Step-by-step explanation:
Using the first statement we can generate the function y=10x + 200 and using the second statement we can also generate the function y = 30x + 100 . Now using the two equations solve for x and y to determine how many months they cost the same.
y = 10x + 200
y = 30x + 100
Substitute the value of x in the first equation into the second equation.
30x + 100= 10x + 200 now solve for x
-100 -100
30x = 10x + 100
-10x -10x
20x = 100
x= 5
This means in five months Tina will save the same amount. Now to find out how much the amount is, plot the value of x into one of the equations and solve for y.
y = 10(5) + 200
y = 50 + 200
y = 250
She will save $250 with either option.