emilyoo 3 years ago How do you find the x intercept??

1. sauravshakya

Substitute y=0

2. sauravshakya

and solve for x

3. emilyoo

its a graph

4. emilyoo

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5. emilyoo

how do you find the x intercept of l?

6. sauravshakya

LET f(x)=0 then solve for x

7. sauravshakya

In this case, 0=10^x

8. emilyoo

im trying to find the x intercept of the unknown line, not f(x)=10^x

9. punnus

@emilyoo in any question intercept means the point of intersection with the respective ... In this case you want the x intercept of l... the equation of l is $10^{x}$ Now for what value of x will will i be zero... Now apply limit to the function of yuors and solve it for -infinity This will give you the x intercept of the curve...

10. sauravshakya

So first find the equation of the line

11. punnus

@emilyoo Does the line and the curve intersect each other on the same point on the y axis?

12. emilyoo

yes

13. emilyoo

at (0,1)

14. emilyoo

and at (log2,2) i think. thats all i know so far

15. hartnn

thats correct, @emilyoo so now u have 2 points on that line,can u find the equation of that line?

16. emilyoo

i got y-1=log2(x)

17. punnus

then toy can find the equation of the line by using the two point formula of line i.e $(y-y1)=\frac{ y2-y1 }{ x2-x1 }\times(x-x1)$ And the arrange the equation in the form x/a+b/b=1 and the value of a will be the x intercept of theline

18. emilyoo

i dont understand how you change the equation in the form x/a+b/b=1... what is b supposed to represent?

19. punnus

a and b are nothing but constants. And first solve the two point equation of the line. You will get a euqation in x, y and some constant value. Now take the constant to one side of the equaltiy and x and y to the other. Divide both the sides by the constant no on one side of the equation and you will get that form

20. hartnn

since u have 2 points : (0,1) and (log 2,2) let the equation be y=mx+c. put (0,1)----->c=1 put (log2,2) 2=m log 2 +1 m=1/(log 2) EQUATION :y=(1/log 2)x+1 x - intercept : 0=(1/log 2)x+1 x=-log 2 is the x-intercept. got this ??

21. punnus

sorry divide the eqn on both the sides

22. punnus

@emilyoo did you get it now

23. emilyoo

ohh...ok i got it now

24. emilyoo

thank you so much

25. hartnn

welcome :)