SOLUTION: 2) e^x + 2x = 7 a) 1.424 b) 7 c) -1.621 d) 3.814 e) None of these

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: 2) e^x + 2x = 7 a) 1.424 b) 7 c) -1.621 d) 3.814 e) None of these      Log On


   

Question 121737: 2) e^x + 2x = 7

a) 1.424
b) 7
c) -1.621
d) 3.814
e) None of these
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Since we have x as an exponent and it is also multiplied by some constant, there is no algebraic way to solve this. So a numerical approximation is the next best thing.

So if we graph y=e%5Ex+%2B+2x and y=7, we get


graph%28500%2C500%2C-10%2C10%2C-10%2C10%2Cexp%28x%29%2B2x%2C7%29 Graph of y=e%5Ex+%2B+2x (red) and y=7 (green)


Now using the "intersect" feature on a calculator, we find that the two graphs intersect at the point (1.424, 7)


So the answer is 1.424 which means the choice is A)