4x² - 12x = 7
- 7 - 7
4x² - 12x - 7 = 0
4x² + 2x - 14x - 7 = 0
2x(2x) + 2x(1) - 7(2x) - 7(1) = 0
2x(2x + 1) - 7(2x + 1) = 0
(2x - 7)(2x + 1) = 0
2x - 7 = 0 or 2x + 1 = 0
+ 7 + 7 - 1 - 1
2x = 7 2x = -1
2 2 2 2
x = 3¹/₂ or x = ⁻¹/₂
Answer:
The answer is B. 581/90
Step-by-step explanation:
just divide 581 by 90 and you'll find that it is equivelent to 6.4<u>5</u>
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Hope that helps!
Answer
Picture? what is the following
Step-by-step explanation:
Answer:
A. -2sin(x)sin(0.4x)
Step-by-step explanation:
At x=0, the given expression evaluates to zero.
For x near zero, the given expression is slightly negative. You know this because cos(1.4x) decreases faster than cos(0.6x), so their difference will be negative.
Of the answer choices, you can eliminate C and D because they are not zero at x=0. You can eliminate choice B, because it is positive for values of x near zero. The only viable choice is A:
-2sin(x)sin(0.4x)
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Of course, a graphing calculator can help you figure this out. See the attachment. The given expression is plotted using a solid red line; the answer choice A is plotted using blue dots.