# Points of intersection

Tags:
1. Oct 14, 2014

### ilii

1. The problem statement, all variables and given/known data

Find the intersection points of y=3x^2 and y=3^x

2. Relevant equations

They must be found with graphing techniques and cannot be proved algebraically. The answers are (-.451,.0609), (1.3), and (3, 27).

3. The attempt at a solution

Table of values from -3 to 3 for x, and i can come up with (1,3) and (3, 27). I really don't know how to find an intersection like (-.451,.0609).

not sure which graph to post here...

for (3x^2)-(3^x)

http://www.meta-calculator.com/online/0gzp2kai8ehf

for y=3x^2 and y=3^x separately

for (3x^2)-(3^x)

http://www.meta-calculator.com/online/0gzp2kai8ehf

for y=3x^2 and y=3^x separately

http://www.meta-calculator.com/online/eqo7hgmc6lsf
and
http://www.meta-calculator.com/online/eqo7hgmc6lsf

Last edited: Oct 14, 2014
2. Oct 14, 2014

### phinds

draw the graph of the lines and post your drawing, else we cannot help you.

3. Oct 14, 2014

### RUber

On your graph of the difference, you can take the zeros. Use those for x and plug back into one of your equations to find y. Otherwise, plot the two functions on the same graph and do your best to estimate.

4. Oct 14, 2014

ok thank you