Sec x is equal to 1/cosx, cot x is equal to cosx/sinx. cos x cancels, and you are left with 1/sinx. this is equal to cscx. Cosecant is : hypotenuse / opposite, so the answer is **D**
Answer: (-9,6)
Step-by-step explanation:
3x+2y=-15
2x=-18
First solve for x in second equation
2x=-18
2x/2=-18/2
X= -9
Now substitute your x into first equation to find y
3(-9)+2y= -15
-27+2y=-15
2y= -15+27
2y= 12
2y/2=12/2
Y= 6
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 :)
Dividing fractions is the same as multiplying by its reciprocal so you can change the equation to this

And you can simplify by eliminating the fours and multiplying straight across

You can pull out - 7 from the top and 2 from the bottom so you have this

And then you can cancel out to (2-x) to get an answer of