15. On the graph of the equation 2x + 5y = −30, what is the value of the y-intercept?
A. 15
B. -15
C. 6
D. -6
17. Given the equation 3x + 25 = 7x − 5, which order of operations completely solves for x?
A. Add 3x, then subtract 25, lastly divide by 10
B. Subtract 3x, then add 5, lastly divide by 4
C. Add 7x, then add 25, lastly divide by 10
D. Subtract 7x, then add 5, lastly divide by 10
23. To which graph does the point (−1, 4) belong?
A. y ≤ −x + 4
B. y ≤ −x − 2
C. y ≤ 2x − 3
D. y≤ 4x + 1
15) We first make the function slope-intercept form:
\(2x+5y = -30 \\5y = -2x-30\\ y = -\dfrac{2}{5}x-6\)
The format for slope intercept form is : y = (slope)x + (y-intercept) or y = mx + b
Now equate the terms: b = -6
Therefore the y-intercept is -6. ANS: D
17) You have to test all those methods on that equation until you found out in one method the last step is x = something.
ANS : B