Solve the equation: 5^(2x+1) = 7, giving your answer correct to four decimal places.

First, we take logs of both sides: log(5^(2x+1))=log(7) Now, using the 3rd law of logs (index rule; using the power as the coefficient), we get: (2x+1)log(5)=log(7) i.e. 2x+1 = (log(7))/(log(5)) = 1.20906... Therefore, 2x=1.209...- 1 = 0.20906... i.e. x = 0.209.../2 = 0.10453... x = 0.1045 (c.t. 4d.p.)

MS
Answered by Mohamad S. Maths tutor

9624 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

What is the integral of ln x dx


A block of temperature H=80ºC sits in a room of constant temperature T=20ºC at time t=0. At time t=12, the block has temperature H=50ºC. The rate of change of temperature of the block (dH/dt) is proportional to the temperature difference of the block ...


Solve algebraically: 2x - 5y = 11, 3x + 2y = 7


Split the following expression into partial fractions of the form A/(x-3) + B/(4x+2) : (19x-15)/(4x+2)(x-3)


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning