Because none of the points on the number line are above 0, we know that the points will be negative.
This eliminates the second and third choices, as they contain positive numbers.
The first point, A, is a number less than -0.5 or -1/2
The first choice matches A with -5/16, which is less than -0.5 or -1/2
Therefore, the fourth choice must be the correct answer.
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 :)
X is Kevin; Y is Dan
X = 3Y
X - 4 = 5(Y - 4)
3Y - 4 = 5(Y - 4)
3Y - 4 = 5Y - 20
+ 4 +4
4 cancels each other out.
3Y = 5Y - 16
- 5 -5
5 cancels each other out.
-2Y = -16
/2 /2
Y = 8
X = 3Y;
X = 3 x 8;
Thus,
X = 24;
Kevin(x) is 24
