Solve for x, z,y
-x + y + 3z = -3
x - 2y - 2z = 8
3x - y - 4z = 6

x = 2, y = -4 , z = 1

Step-by-step explanation:

-x + y + 3z = -3 - - - - - - - - - - 1

x - 2y - 2z = 8 - - - - - - -- - - - 2

3x - y - 4z = 6 - - - - - - - - - - - - - 3

Let us use the method of elimination

We would add equation 1 to equation 2. It becomes

-y+z= 5 - - - - - - - - - - - - - - -4

Multiply equation 2 by 3 and equation 3 by 1

3x - 6y -6z = 24- - - - - - - - - - 5

3x - y - 4z = 6 - - - - - - - - - - - - -6

Subtracting equation 6 from equation 5

-5y -2z = 18 - - - - - - - - - - 7

Substituting z = 5 + y into equation 7, it becomes

-5y -2(5+y) = 18

-5y -10-2y = 18

-5y -2y = 18+10

-7y = 28

y = 28/-7 = -4

z = 5 + y

z = 5 -4 = 1

We would substitute y = -4 and z = 1 into equation 2

It becomes

x - 2×-4 - 2×1 = 8

x+8-2 = 8

x +6 = 8

x = 8-6 = 2

x = 2, y = -4 , z = 1

Let us check by substituting the value into equation 1

-x + y + 3z = -3

-2-4+ 3= -3

-6 + 3 = -3

-3 = -3

answer: city needs 2.4 inches of rainfall more to match the record of 40 inches.

step-by-step explanation:

since we have given that

total annual rainfall a city record = 40 inches

this year, total rainfall recorded = 37.6 inches

number of inches of rainfall   is needed to match the record of 40 inches is given by

hence, city needs 2.4 inches of rainfall more to match the record of 40 inches.

i believe the answer is d.

hope it you! : d