Answer:
n = -12
Step-by-step explanation:
(-2/3)n + 7 = 15
(-2/3)n+7-7 = 15-7 Subtract by 7 on both sides
(-2/3)n = 8 Multiply by the reciprocal of the fraction, which is
(-2/3)n*(-3/2) = 8(-3/2) This makes it so you get n *1 and isolates n.
n = -24/2 = -12
The Pythagorean theorem tells you ...
... c² = a² + b²
... 13² = 12² + b² . . . . . fill in the given numbers
... 169 - 144 = b² . . . . .subtract 12²
... √25 = b . . . . . . . . . take the square root
... b = 5 . . . . . . The value of b you're looking for.
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The numbers {5, 12, 13} make what is called a "Pythagorean triple" a set of integers that satisfies the relation of the Pythagorean theorem. These, and the triple {3, 4, 5} are often seen in algebra problems. It can be worthwhile to remember these numbers.
Answer:

Step-by-step explanation:

Remove parenthesis:

Separate the constants:

Simplify:


Choice B because when you use distributive property, you'll get 3x+3x+3y*3x+3x+3y