Solve -4(x + 1) – 3 = -3(x - 4).

We have this equation:

-4(x+1) - 3 = -3(x-4)

First of all, we solve the paretheses:

-4x - 4*1 - 3 = -3x - (-3*4)

-4x - 4 - 3 = -3x +  12

-4x -7 = -3x + 12

We sum 7 on both sides and 3x on both too:

-4x - 7 + 7 + 3x = -3x + 12 + 3x + 7

-4x + 3x = 12 + 7

-x = 19

x = -19

Now we can verify:

-4(-19+1) - 3 = -3(-19-4);

-4(-18) - 3 = -3(-23);

72 - 3 = 69 (TRUE)

true

step-by-step explanation:

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.