I do believe it is 12 as well considering the fact that it's negative three and not positive. If it was a positive three then maybe it would be 18.
Hello from MrBillDoesMath!
Answer:
The first choice ( -12, 20)
Discussion:
Using matrix multiplication we find the equations:
1x + 1y = 8 (A)
2x + 3y = 36 (B)
Next, compute
2(A) - B =>
(2x + 2y) - (2x + 3y) = 2*8 - 36 =>
(2x - 2x) + ( 2y-3y) = 16 - 36 =>
-y = -20 =>
y = 20
Substituting this y value in (A) gives
x + 20 = 8 =>
x = 8 - 20 =>
x = -12
The answer is the first choice ( -12, 20)
Thank you,
MrB
Answer: 3 copies of 5 tenths = 3*0.5 = 1.5
Step-by-step explanation:
Ok, if we have:
"3 copies of a number B"
This is written as:
3*B
And we have that the number B is "5 tenths"
Now, a tenth is the first digit after the decimal point.
Then 5 tenths = 5*0.1 = 0.5
B = 0.5
3 copies of 5 tenths = 3*0.5 = 1.5
Let A represent the amount Ann contributed, Z represent Zoe's contribution, and J represent Jim's contribution toward the present.
Ann (A): A
Zoe (Z): A = Z - 12 → Z = 12 + A
Jim (J): A = J - 16 → J = 16 + A
A + Z + J = 154
(A) + (12 + A) + (16 + A) = 154
3A + 28 = 154
3A = 126
A = 42
Ann (A): A = 42
Zoe (Z): Z = 12 + A = 12 + 42 = 54
Jim (J): J = 16 + A = 16 + 42 = 58
Answer: Ann=42, Zoe=54, Jim=58