Question

Part A: Explain why the x-coordinates of the points where the graphs of the equations y = 8x and y = 2x + 2 intersect are the solutions of the equation 8x = 2x + 2. (4 points)

Part B: Make tables to find the solution to 8x = 2x + 2. Take the integer values of x between −3 and 3. (4 points)

Part C: How can you solve the equation 8x = 2x + 2 graphically? (2 points)

Answer 1

@Qwertty123 can you help with this one?

Answer 2

if they y values are the same then you can equate these 2 equations

y = 8x and y = 2x + 2
8x=2x+2

Answer 3

The first graph is the set of all points where y = 8x. The second graph is the set of points where y = 2x + 2. If a point is on both graphs, then both equations will be true at the same time. So we will have 8x = y and y = 2x + 2, so 8x = 2x + 2.
@jameshorton said above! :D

Answer 4

(B)
x . 8x . 2x + 2
-3 . -24 . -4
-2 . -16 . -2
-1 . -8 . . 0
0 . . 0 . . 2
1 . . 8 . . 4
2 . 16 . . 6
3 . 24 . . 8

From this you can see that the solution is between 0 and 1. Using algebra we can solve it easily:
8x = 2x + 2
=> 6x = 2
=> x = 1/3.

Answer 5

wow you are fast!

Answer 6

Part C? Do you know what you have to do? (C) Graph the two lines from part A and find the x-coordinate of the intersection.

Answer 7

First i have a question about Part b and for part c i dont have any graphs to do this on.

Answer 8

what do the dot mean in part b?

Answer 9

@Qwertty123

Answer 10

graph 1 => y = 8^x
graph 2 => y = 2^x +2
plug in different x's between -3 and 3 .... and find different y's corresponding to those x's...
when the y's become equal ...
it will be the required solution .... that x is the solution.

Answer 11

is this part b or part c

Answer 12

okay so that was the table then?

Answer 13

LOL I am getting confused! XD @welshfella

Answer 14

me too

Answer 15

@tHe_FiZiCx99

Answer 16

i dont see how you are confused @Qwerty123
You've answered the question perfectly

Answer 17

I did? Oh....lol...To be honest my brain is not awake yet...