Twice a number plus three times a second number is negative one. The first number plus four times the second number is two.

The first number is -2 and the second number is 1.

Step-by-step explanation:

2n + 3s = -1

(n + 4s = 2)-2             Multiply by -2 to cancel the n

2n + 3s = -1

-2n - 8s = -4               Add these equations together

-5s = -5                      Divide both sides by -5

s = 1

Plug this into the first equation to find the value of n

2n + 3(1) = -1              Multiply

2n + 3 = -1

     - 3    - 3                Subtract 3 from both sides

2n = -4                       Divide both sides by 2

n = -2

1. sometimes

2. never true

3. sometimes

step-by-step explanation:

these are pretty self explanatory if you know what supp right and com angles are

just sum

10 + 10 = 20