The US postal service delivered 7.14 x 1010 pieces of mail in the month of December 7.14 x 1010=7211.4
3.21 x 1010 in the month of January. 3242.1
What is the total mail delivered for these two months?
7211.4
+ 3242.1
__________
10453 .5 TOTAL MAIL
SOLUTION
Given the question in the image, the following are the solution steps to answer the question.
STEP 1: Write the given function

STEP 2: Plot the given function
STEP 3: choose the correct graph
It can be seen from the plotted graph in step 2 that:

Hence, comparing the x-intercepts, the correct graph is seen in:
3x - y + z = 5 . . . (1)
x + 3y + 3z = -6 . . . (2)
x + 4y - 2z = 12 . . . (3)
From (2), x = -6 - 3y - 3z . . . (4)
Substituting for x in (1) and (3) gives
3(-6 - 3y - 3z) - y + z = 5 => -18 - 9y - 9z - y + z = 5 => -10y - 8z = 23 . . (5)
-6 - 3y - 3z + 4y - 2z = 12 => y - 5z = 18 . . . (6)
(6) x 10 => 10y - 50z = 180 . . . (7)
(5) + (7) => -58z = 203
z = 203/-58 = -3.5
From (6), y - 5(-3.5) = 18 => y = 18 - 17.5 = 0.5
From (4), x = -6 - 3(0.5) - 3(-3.5) = -6 - 1.5 + 10.5 = 3
x = 3, y = 0.5, z = -3.5
Answer:
I did not understand its confusing
3ab - 3a - 8 + 4ab + 8
7ab -3a