Answer:
C.
Step-by-step explanation:
The highest term must be of x^4, then decreasing to x^3, x^2, x and the constant term.
Altogether there are at maximum 5 terms.
<span>5×70=5× 7 tens
=35 tens =350
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It has become somewhat fashionable to have students derive the Quadratic Formula themselves; this is done by completing the square for the generic quadratic equation ax2 + bx + c = 0. While I can understand the impulse (showing students how the Formula was invented, and thereby providing a concrete example of the usefulness of abstract symbolic manipulation), the computations involved are often a bit beyond the average student at this point.
4 - 5x = 2x + 25
4 = 7x + 25
-21 = 7x
-3 = x
4 - 5x + 2x + 25 = ac
4 - 5(-3) + 2(-3) + 25 = ac
4 - (-15) + (-6) + 25 = ac
19 + (-6) + 25 = ac
38 = ac
