Answer:
<h2>f(x) = 3x + 4</h2>
Step-by-step explanation:
f(x + 1) = 3x - 7
f(x) = f(x + 1 - 1) = 3(x - 1) + 7 = 3x - 3 + 7 = 3x + 4
Check
f(x) = 3x + 4
f(x + 1) = 3(x + 1) + 4 = 3x + 3 + 4 = 3x + 7 CORRECT
Answer: 
Step-by-step explanation:
By definition, an Isosceles triangle has two equal sides and its opposite angles are congruent.
Observe the figure attached, where the isosceles triangle is divided into two equal right triangles.
So, in this case you need to use the following Trigonometric Identity:

In this case, you can identify that:

Substituting values, and solving for "x", you get:

Therefore, the length of BC rounded to nearest tenth, is:

Answer:
length = 17cm, width = 10cm
Step-by-step explanation:
2L + 2w = 54
L = w + 7
Substitute:
2(w + 7) + 2w = 54
2w + 14 + 2w = 54
4w = 40
w = 10
L = 10 + 7 = 17
Answer:
It would be B!
Step-by-step explanation:
D has an obtuse angle, so it can be eliminated.
C has angles that are not vertical, but rather adjacent. Same goes for A!
Hope this helps!
The answer is: [A]: 45x² + 81x + 36 .
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Explanation: Use "FOIL" technique: (First, Outer, Inner, and Last Terms);
then, combine the "like terms", to simplify.
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(5x+4)(9x+9) = 45x² + 45x + 36x + 35 = 45x² + 81x + 36 .
(which is answer choice: "A".).
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