Answer:
b. (1, 3, -2)
Step-by-step explanation:
A graphing calculator or scientific calculator can solve this system of equations for you, or you can use any of the usual methods: elimination, substitution, matrix methods, Cramer's rule.
It can also work well to try the offered choices in the given equations. Sometimes, it can work best to choose an equation other than the first one for this. The last equation here seems a good one for eliminating bad answers:
a: -1 -5(1) +2(-4) = -14 ≠ -18
b: 1 -5(3) +2(-2) = -18 . . . . potential choice
c: 3 -5(8) +2(1) = -35 ≠ -18
d: 2 -5(-3) +2(0) = 17 ≠ -18
This shows choice B as the only viable option. Further checking can be done to make sure that solution works in the other equations:
2(1) +(3) -3(-2) = 11 . . . . choice B works in equation 1
-(1) +2(3) +4(-2) = -3 . . . choice B works in equation 2
Answer:
8 one-dollar bills
3 five-dollar bills
2 ten-dollar bills
Step-by-step explanation:
Let x = # of one-dollar bills, y = # of five-dollar bills, and z = # of ten-dollar bills. Total amount in the wallet is $43, so the first equation would be 1x + 5y + 10z = 43. Next, there are 4 times as many one-dollar bills as ten-dollar bills, so x = 4z. There are 13 bills in total, so x + y + z = 13
x + 5y + 10z = 43
x = 4z
x + y + z = 13
x + 5y + 10z = 43
x + 0y - 4z = 0
x + y + z = 13
5y + 14z = 43
-y - 5z = -13
5y + 14z = 43
-5y - 25z = -65
-11z = -22
z = 2
x = 4z
x = 4*2 = 8
x + y + z = 13
8 + y + 2 = 13
10 + y = 13
y = 3
We know that
the axis is equal to the diameter of a sphere
so
D=14 units
r=D/2-----> r=7 units
<span>the surface area of the sphere=4*pi*r</span>²------> 4*pi*7²=196*pi units²
the answer is the option
<span>C. 196 pi units^2</span>
Answer:
48 years old and Devaughn is 41
Step-by-step explanation:
math
The total area is 625 because 25 x 5 = 125. 125 x 5 = 625. that is how you get your answer
