Tuesday

September 23, 2014

September 23, 2014

Posted by **Gingie** on Friday, July 11, 2014 at 6:48pm.

(sqrt of 4x+1)+(sqrt of x+1)=2

Someone showed me to do this next:

Square both sides..so..

4x+1+2((sqrt of 4x+1)•(sqrt of x+1))=4

I do not understand where the 2 come from ..and why do we need to multiply the sqrt of 4x+1 and sqrt of x+1 together to get the product.......??????????

- Surds -
**Gingie**, Friday, July 11, 2014 at 6:49pmWhoops I meant ..

Sqrt of x+3, not x+1..

- Surds -
**DrBob222**, Friday, July 11, 2014 at 7:26pm(a+b)^2 = a^2 + ab + b^2

- Surds -
**bobpursley**, Friday, July 11, 2014 at 7:53pma+b)^2 = a^2 + 2ab + b^2

(sqrt of 4x+1)+(sqrt of x+3)=2

4x+1 + 2 (sqrt (x+3)sqrt(4x+1)) + x+3=4

5x+4 +2 (sqrt (5x+4)=4

5x+2sqrt(5x+4)=0

5x=-2(sqrt(5x+4)

square both sides

25x^2=4(5x+3)

25x^2-20x-12=0

(5x+2)(5x-6)=0

x=-12/5 or x=6/5

check that.

- Surds -
**Steve**, Friday, July 11, 2014 at 8:44pmHmmm. I get

√(4x+1)+√(x+3)=2

4x+1 + 2√(4x^2+13x+3) + x+3 = 4

5x = -2√(4x^2+13x+3)

25x^2 = 4(4x^2+13x+3)

25x^2 = 16x^2 + 52x + 12

9x^2 - 52x - 12 = 0

(9x+2)(x-6) = 0

x = -2/9 , 6

But x=6 does not satisfy the original equation, so -2/9 is the only solution.

**Answer this Question**

**Related Questions**

Math Help please!! - Could someone show me how to solve these problems step by ...

math calculus please help! - l = lim as x approaches 0 of x/(the square root of...

Algebra - Solve for s: h=(square root of 3)times s/2 and solve for h V= (pi)r ...

Math - How do you find a square root of a number that's not a perfect square? I'...

math,algebra,help - Directions are simplify by combining like terms. x radiacal ...

Math(Roots) - sqrt(24) *I don't really get this stuff.Can somebody please help ...

MATH - I need to simply this equation, but I got stuck. h/(4-sqrt(16+h)) = y ...

math - solve 2x^2+3x+8=0 and express the solutions in a+bi form. Let's use the ...

math - determine the area of triangle abc when side ab= square root of x, side ...

Inequality - When I solve the inquality 2x^2 - 6 < 0, I get x < + or - ...