Question

Pls help with my math! It’s the end of the year and I’m having a hard time trying to finish on time!

Answer 1

Explanation:

5). 3x + y = 5 -------(1)

2x - y = 10 ---------(2)

By adding equation (1) and (2),

(3x + y) + (2x - y) = 5 + 10

5x = 15

x = 3

From equation (1),

3(3) + y = 5

y = -4

6). 4x + 3y = 13 -------(1)

x + y = 4 -------(2)

Multiply equation (2) by 3 and subtract it from equation (1)

(4x + 3y) - (3x + 3y) = 13 - 12

x = 1

From equation (2),

1 + y = 4

y = -3

7). x - 7y = 7 -----(1)

-3x + 21y = -21

-3(x - 7y) = -(3 × 7)

x - 7y = 7 -------(2)

Since, equation (1) and (2) are same, system of the equations will have infinitely many solutions.

8). x - 3y = 12

3y = x - 12

`y=(1)/(3)x-4` --------(1)

3x - 9y = 18

3(x - 3y) = 3(6)

x - 3y = 6

3y = x - 6

`y=(1)/(3)x-2` ----------(2)

Slopes of both the equations are same but the y-intercepts are different.

Therefore, both the lines are parallel and the system of equations will have no solution.