Answer:
D. -20 + 35c
Step-by-step explanation:
<em><u>All you need to do is distribute the -5 to what's inside the parenthesis:</u></em>
-5(4 - 7c)
<em><u>The -5 can be distributed to the 4 and the -7c:</u></em>
-20 + 35c
Hope you can read this and hope it helps
From the system of equations, we have 3 unknowns and 3 equations. Therefore, it can be solved.
<span>3x - 2y + 2z = 30 (1)
</span><span>-x + 3y - 4z = -33 (2)
</span><span>2x - 4y + 3z = 42 (3)
We can write equation 2 x as a function of y and z and substitute the new equation to the other equations.
</span>x =3y - 4z + 33 (2)
3 (3y - 4z + 3)<span> - 2y + 2z = 30 (1)
</span>2 (3y - 4z + <span>3)</span> - 4y + 3z = 42 (3)
We simplify and solve the equations and we get values,
x = 4
y = -7
z = 2
A theorem requires a proof.
