Funadvice Logo
Explore Join
More Education & School Questions

How can I do this advanced math problem?

Anyone knows how to do this problem? I need help and fast. Solve for x. 2^2x-10(2^x)+16=0

Thanks in advance.

Become an Expert →
Answer #1

Homework questions ARE allowed, but this one is a tad confusing. (Although I do not think anyone here is going to do your homework, we can help and give hints.)

Is it (2 raised to the 2x power) minus (10 times the quantity 2 to the x power) + 16 = 0 In other words subbing ‘n’ for ‘x’ is this what you are asking

2²ⁿ - 10(2ⁿ) + 16 = 0

Could the answer be simplified and solved as follows??? (2²)ⁿ - 20ⁿ + 16 = 0 (4)ⁿ - 20ⁿ + 16 - 16 = 0 - 16 4ⁿ - 20ⁿ = -16 -16ⁿ = -16 Therefore n=1

I really don’t know if that is correct math. It has been to long since I played with exponents.

I hope this helped, but I’m not sure… Good Luck!! (I changed ‘x’ to ‘n’ because ALT codes have a superscript ‘n’ but not ‘x’) Beauty Queen, let me know if this was correct, will you please?

Answer #2

sorry bimjob but just part of your working was wrong. The last 2 steps to be precise. Oh! And the first step. But good try. This problem is not as tricky as it seems. Let me show you.

2^(2x) - 10(2^x) + 16 = 0 (2^x)^2 - 10(2^x) + 16 = 0 [ Then make the substitution y = 2^x ] y^2 - 10y + 16 = 0 (y -2)(y-8) = 0 therefore y = 2 or y =8 this means that 2^x = 2 or 2^x = 8 therefore x = 1 or x = 3.

There you go. =)

More Like This
Ask an advisor one-on-one!
Advisor

Kids Math Games

Education, Children's Entertainment, Online Games

Advisor

Fun Math Games for Kids

Education, Children's Entertainment, Online Learning

Advisor

معهد التدريب العربي للتكنولوجيا

تدريب مهني, تدريب هندسي, تدريب كهربائي

Advisor

No Fuss Tutors

Education, Tutoring Services, Online Learning

Advisor

Elite Tutors Sussex

Education, Tutoring, Mathematics