9514 1404 393
Answer:
+70 or -70, depending on how you rewrite the equation
Explanation:
A quadratic equation in standard form can be written as ...
ax² +bx +c = 0
When this equation is written in standard form, it could be either of ...
17x² +30x +40 = 0 . . . . . . . . . . add 17x²+30x to both sides
or
-17x^2 -30x -40 = 0 . . . . . . . . . subtract 40 from both sides
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In the first case, a = 17, b = 30, c = 40 and (b+c) = 70.
In the second case, a = -17, b = -17, c = -40 and (b+c) = -70.
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Additional comment
I personally prefer a positive leading coefficient, but it is less work to subtract 40 from both sides than to subtract 2 terms from both sides. Check your curriculum materials for the preferred rewrite in this case.