algebra *grr*?
Hi i need some help solving equations with rational expressions im in 9th grade(if that matters or not idk) this is kicking my butt! Im like (WHY CANT I GET THIS!!) i feel so dumb... so here goes...oh teah and they need to be simplified...
1. 5over y-2 equals y+2
2. x over 3 minus 2 over 3 equals 1 over x
3. y+2 over y equals 1 over y-5
4. x^2 over x-4 minus 7 over x-4 equals 0
5. x^2 over x+3 minus 5 over x+3 equals 0
Thank you all for your help!!
Comments
5/(y-2)=y+2
5=y^2-4
y=9
y=3, -3
x/3-2/3=1/x
(x-2)/3=1/x
x-2=3/x
x^2-2x=3
x^2-2x-3=0
(x-3)(x+1)=0
x=3,-1
1. rewrite as 5/(y-2) = y+2
Get rid of the (y-2) on the left hand side by multiplying both sides by (y-2).
therefore becomes 5=(Y-2)(Y+2)
then multiply out the brackets on the right hand side.
so you get:
(yxy)+(yx2)+(-2xy)+(-2x2) = Y^2 (means y squared) + 2y+(-2y) +(-4) = y^2 +2y - 2y -4
which becomes y^2 -4
so now the equation in question is 5 = y^2 - 4
Plus 4 on both sides
becomes 9 = y^2
to make Y^2 become just y you square root both sides to get y=3. because square root of 9 is 3 yeh!!
1. times both sides by y-2 to cancel out the over 2 so you have 5=y^2 divide by y so you get.................
5 over y = y