11. You’ve done it correctly
12. Let x^2=y
y^2+13y+40=0
(y+8)(y+5)=0
y=8, 5
Since y=x^2
x^2=8 x^2=5
x=+/-√5 x= +/-2√2
13. x^4-x^2-x^2-8=0
x^4-2x^2-8=0
let x^2=y
Y^2-2y-8=0
(y-4)(y+2)=0
y=4, -2
Since y=x^2
X^2=4 X^2=-2
X= +/- 2 This wouldn’t be a real solution
14. It’s pretty much the same process, just substitute y in for x^2. If you’re confused feel free to ask and I can do it, or you can put it through Photomath
15. You’re on the right track so I’m just going to continue from where you left off
x^2(4x+5)-4(x+5)=0
(x^2-4)(4x+5)=0
x= +/- 2 4x=5
x=5/4 or 1 1/4
Hope this helped :)
3x and 2x are alike terms, as they have the same variable
Answer:
1 is a whole number, an integer, and rational.
Step-by-step explanation:
Answer:
x = 5
Step-by-step explanation:
3x - 7 + 4x = 28
Combine like terms
7x -7 = 28
Add 7 to each side
7x - 7 +7 = 28+7
7x = 35
Divide each side by 7
7x/7 = 35/7
x = 5
The solution is 2x-7 is 78
