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33 votes
33 votes
Can someone help
me with this and explain how you got it?

Can someone help me with this and explain how you got it?-example-1
User Jakedunc
by
2.9k points

2 Answers

22 votes
22 votes

Answer:

111

Explanation:

2^3[2^(x+1) + 2^(x+4) - 2^(x+2) - 2^(x-3)] =

2^(x+4) + 2^(x+7) - 2^(x+5) - 2^x =

2^x (2^4 + 2^7 - 2^5 -1) =

2^x (16+128-32-1) =

2^x (111) =

111 × 2^x = a × 2^x

so, the value of a = 111

User James Kingsbery
by
2.9k points
18 votes
18 votes

Answer:

a = 111

Explanation:

Given expression:


2^3(2^(x+1)+2^(x+4)-2^(x+2)-2^(x-3))


\textsf{Apply exponent rule} \quad a^(b+c)=a^b \cdot a^c


\implies 2^3(2^x \cdot 2^1+2^x \cdot 2^4-2^x \cdot 2^2-2^(x-3))


\textsf{Apply exponent rule} \quad a^(b-c)=(a^b)/(a^c)


\implies 2^3\left(2^x \cdot 2^1+2^x \cdot 2^4-2^x \cdot 2^2-(2^x)/(2^3)\right)

Simplify:


\implies 8\left(2^x \cdot 2+2^x \cdot 16-2^x \cdot 4-2^x \cdot (1)/(8)\right)

Factor out
2^x :


\implies 8\left(2^x \left[2+16-4- (1)/(8)\right]\right)

Simplify:


\implies 8\left(2^x \left[(111)/(8)\right]\right)


\implies 111 \cdot 2^x

Therefore, a = 111

User JD Frias
by
2.6k points