SOLUTION: Solve the following exponential equations: a) 7^x=49 b) 243 = 9^2x+1 c) 2^2x * 4^4x +8 = 64 d)9^x-1 * 81 ^2x-1 = 27^3x-2

Algebra.Com
Question 634606: Solve the following exponential equations:
a) 7^x=49
b) 243 = 9^2x+1
c) 2^2x * 4^4x +8 = 64
d)9^x-1 * 81 ^2x-1 = 27^3x-2

Found 2 solutions by ewatrrr, lwsshak3:
Answer by ewatrrr(24785)   (Show Source): You can put this solution on YOUR website!
 
Hi,
the idea is to have the base numbers the same ⇒ Exponents are Equal
a) 7^x=49 ⇒ 7^x = 7^2 ⇒ x = 2
b) 243 = 9^2x+1 ⇒ ⇒ 5 = 2(2x+1), x = 3/4
c) 2^2x * 4^4x +8 = 64 ⇒ , x= -1
d)9^x-1 * 81 ^2x-1 = 27^3x-2 ⇒ x = 0
Answer by lwsshak3(11628)   (Show Source): You can put this solution on YOUR website!
Solve the following exponential equations:
a) 7^x=49
7^x=7^2
x=2
..
b) 243 = 9^(2x+1)
3^5=3^2^(2x+1)
3^5=3^(4x+2)
4x+2=5
4x=3
x=3/4
..
c) 2^2x * 4^(4x +8) = 64
2^2x * 2^2(4x+8) =2^6
2^2x*2^(8x+16)=2^6
2^(10x+16)=2^6
10x+16=6
10x=-10
x=-1
..
d)9^(x-1) * 81 ^(2x-1) = 27^(3x-2)
9^(x-1) * 9^2 ^(2x-1) = 3^3^(3x-2)
9^(x-1) * 9^(4x-2) = 3^3^(3x-2)
3^2^(x-1) * 3^2 ^(4x-2) = 3^3^(3x-2)
3^(2x-2)*3^(8x-4)=3^(9x-6)
3^(10x-6)=3^(9x-6)
10x-6=9x-6
x=0

RELATED QUESTIONS

Solve x in the following exponential notation {{{9^(x-1) *... (answered by lwsshak3)
exponential equations 4^3x-3=8^4x-4, 9^-X-5=27^6x-10, 125^3x-4=25^4x+2,... (answered by ewatrrr)
Please help :) Evaluate: a) [(81/16)^(1/4) - (1/3)^0]^-2 --I got ??... (answered by edjones)
Solve # 25 – 34 Show Work Please if possible. 25. 32^2x-3 = 2 26. 9^2x+1 = 81... (answered by Alan3354)
Solve each of he exponential equations by finding a common base. a) (4/9)^x=27/8 b) (answered by greenestamps,josgarithmetic)
9^(x-1)*81^(2x-1)... (answered by Earlsdon)
Solve for x in the following. A) 3^x=27 B) 16^x=64 C) 2=(1/32)^x D)... (answered by MathLover1)
Solve x in the following exponential notation... (answered by Earlsdon,MathLover1,DrBeeee)
Which of the following equations is a quadratic equation ? a. y = x^2 + 4 b. y =... (answered by stanbon)