In slope-intercept form, what is the equation of the line containing the points (−1, 2) and (2, −1)? a
y = −x + 1

b
y = x + 1

c
y = −x + 3

d
y = −x − 1

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.