Help with 5 algebra problems?

Question

1. f(-3) f(x) = {-x²+2x, x<1}

{-2x+3, x>1}

2. Tell how many solutions the linear system has(infinitely,one, or none)

x-4y=2

x+4y=2

3. Solve the linear system:

3x+4y=-10

-3x+y=5

4. Solve the system

3x+4y=-3

2x+y=8

5. Solve the linear system

7x-4y=12

3x+2y=4

THANK YOU!

Answer 1

Since x = -3, which is less than 1, use the first equation.

f(-3) = -(-3)²+2(-3)

f(-3) = -9+-6

f(-3) = -15

x-4y=2

x+4y=2

-----------

2x + 0y = 4

2x = 4

x = 2

one solution

3x+4y=-10

-3x+y=5

----------------

0x + 5y = -5

5y = -5

y = -1

3x+4(-1)=-10

3x + -4 = -10

3x = -6

x = -2

(-2, -1)

-4(2x+y=8)

-8x + -4y = -32

3x + 4y = -3

----------------------

-5x + 0y = -35

-5x = -35

x = 7

3(7) + 4y = -3

21 + 4y = -3

4y = -24

y = -6

(7, -6)

2(3x+2y=4)

6x + 4y = 8

7x - 4y = 12

------------------

13x + 0y = 20

13x = 20

x = 20/13

6(20/13) + 4y = 8

120/13 + 4y = 8

4y = 104/13 - 120/13

4y = -16/13

y = (-16/13)(1/4)

y = -4/13

(20/13, -4/13)

Hope that helps!