Monday

January 26, 2015

January 26, 2015

Posted by **gabs** on Tuesday, June 7, 2011 at 10:56pm.

x^2 + y^2 = 36

y= x+b

and then they give me an answer box

b=_________ (smaller value)

b=_________ (larger value)

i have absolutely no idea how to even begin this and what they are asking. could some please help and explain what im supposed to do with this. thanks so much!!!

- pre calc -
**Reiny**, Tuesday, June 7, 2011 at 11:20pmsub in the straight line into the circle

x^2 + (x+b)^2 = 36

x^2 + x^2 + 2bx + b^2 - 36 = 0

for one solution the discriminant, that is

b^2 - 4ac = 0

(2b)^2 - 4(2)(b^2-36) = 0

4b^2 - 8b^2 + 288=-

-4b^2 = -288

b^2 = 72

b = ± √72 or ± 6√2

- pre calc -
**Mgraph**, Tuesday, June 7, 2011 at 11:37pmDraw two tangents to the circle x^2+y^2=6^2 parallel to the line y=x in the second and fourth quadrants.

b is y-intercept of these tangents.

Сonsider the algebraic method.

Find the coordinates of common points of the line and circle:

x^2+(x+b)^2=36

2x^2+2bx+b^2-36=0

Since the line is tangent then the equation has unique solution =>

the discriminant (2b)^2-4*2(b^2-36)=0

4b^2-8b^2+288=0

b^2=72

b=6sqrt(2) or b=-6sqrt(2)

- pre calc -
**Mgraph**, Tuesday, June 7, 2011 at 11:52pmConsider the geometric method.

b(b>0)- is the leg in a isosceles rectangular triangle with height=6

6^2+6^2=b^2

**Answer this Question**

**Related Questions**

PRE CALC - Use matrices to solve the system. (If the system has infinitely many ...

CHEMISTRY (WEBWORK) - SPARTAN: Enter the numerical energy values (X, Y, & Z) on ...

Pre-Calc - An open box with a volume of 1500cm^3 is to be constructed by taking ...

calc - analyze the function ln x = cx^2 to find the unique value of c such that ...

stats - i need help with this Question The following data represents Total ...

STATS - i need help with this Question The following data represents Total ...

math - two systems of equations are giving below for each system choosethe best ...

Pre-Calc - Can you show me how to find the rectangular equation of r=2costheta...

pre calc - What is the vertical and horizontal asymptotes of .. 3x _________ x^2...

Calculus Please Help - Can someone please tell me how to do these? Suppose that ...