8th grade algebra: radicals
posted by jenna on .
please help me solve these
1. 2√5/8 + 4√3/8  1/2√68
2. √4k5 +1=8
(the radical sign goes over 4k5)
3. (x+4)*2 /3 =8
4. Write the value of the discriminant of each equation. Then use it to decide how many different realnumber roots the equation has.
x*26x+2=0

Answer to number 3:
2/3(x+4) = 8
2(x+4) = 24
2x+8 = 24
2x = 16
x = 8 
Answer to number 3 is wrong. (didn't realise it was x+4 to the power of two thirds. Sorry):

Looks like Jenna is using * as the sign for exponents.
In #3 , no brackets were used around the 2/3, so it has to be read as
((x+4)^2)/3 = 8
then
(x+4)^2 = 24
x+4 = +/ sqrt(24)
x = 4 +/ 2sqrt(6)