Which expression is equivalent? 8(3x − 6) A) 24x + 48 B) 24x − 48 C) −24x + 48 D) −24x − 48
2 answers:
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Answer:
Step-by-step explanation:
My favorite way to go at this is to look at a graph. It shows the vertex at (-2, -11). Since the leading coefficient is 2, this means the roots are ...
where the 2 in the denominator of the radical is the leading coefficient.
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You can also use other clues:
- the axis of symmetry is -b/(2a) = -8/(2(2)) = -2, so answer choices C and D don't work
- the single change in sign in the coefficients (+ + -) tells you there is one positive real root, so answer choice B doesn't work.
The first answer choice is the only one with values symmetrical about -2 and one of them positive.
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You may be expected to use the quadratic formula:
Answer:
y=25.5
Step-by-step explanation:
To find y, you need to get it by itself. Ask yourself, what is being done to y, then to undo that, do the opposite. For example, if 3 was added to y, you would need to subtract 3 to cancel out the 3. In this case, what is being done to y? It's being divided by 3. So, you multiply by 3 to cancel that out. Whatever you do to one side of an equation, you also have to do to the other. So,
8.5= Multiply both sides by 3
3(8.5) = 3() multiply on the left side, and on the right side the 3s cancel out
25.5=y