Solve the system or linear equations

37. {-1, -1}.

Step-by-step explanation:

I'll solve the first one . The other can be solved in a similar way. We can use the method of elimination.

x1 - x2 = 0

3x1 - 2x2 = -1

We can multiply the first equation by -2. We then have an equation containing + 2x2 so when we add this to the second equation the 2x2 will be eliminated

So the first equation becomes:

-2x1 + 2x2 = 0     Bring down the second equation:

3x1 - 2x2 = -1       Now adding, we get:

x1 + 0 = -1

so x1 = -1.

Now we substitute this value of x1 in the original first equation:

-1 - x2 = 0

-1 = x2

x2 = -1.

So the solution set is {-1, -1}.

If there are more than 2 equations you can use a combination of substitutions and eliminations.

2.2°  

step-by-step explanation:

let θ = the angle of elevation.

tanθ =77/2020

tanθ = 0.038 12

      θ = tan⁻¹0.038 12

      θ = 2.2°

c

-by-step explanation:

it would be c