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 :)
Coral reef = 0.15x
0.15(11) = 1.65
1 meter = 100 cm
1.65 * 100 = 165
Solution: 165 cm
They will cost $54
i know this because if youre getting 40% off, you will have to pay 60% of the total cost
so, 90 x .60 = 54
let me know if you have any further questions
:)
Answer:
Step-by-step explanation:
Term Definition
Linear regression line The line that goes through a set of points either exactly or approximately.
Difference The result of a subtraction operation is called a difference.