Answer:
5
Step-by-step explanation:
AC=AB+BC
so 16=x+1+x+7
which simplifies to 16=2x+8
subtract eight from both sides to get 8=2x
then divide by 2 to get that x=4
AB=x+1, which substitutes into 4+1=5
Answer:
Verified below
Step-by-step explanation:
We want to show that (Cos2θ)/(1 + sin2θ) = (cot θ - 1)/(cot θ + 1)
In trigonometric identities;
Cot θ = cos θ/sin θ
Thus;
(cot θ - 1)/(cot θ + 1) gives;
((cos θ/sin θ) - 1)/((cos θ/sin θ) + 1)
Simplifying numerator and denominator gives;
((cos θ - sin θ)/sin θ)/((cos θ + sin θ)/sin θ)
This reduces to;
>> (cos θ - sin θ)/(cos θ + sin θ)
Multiply top and bottom by ((cos θ + sin θ) to get;
>> (cos² θ - sin²θ)/(cos²θ + sin²θ + 2sinθcosθ)
In trigonometric identities, we know that;
cos 2θ = (cos² θ - sin²θ)
cos²θ + sin²θ = 1
sin 2θ = 2sinθcosθ
Thus;
(cos² θ - sin²θ)/(cos²θ + sin²θ + 2sinθcosθ) gives us:
>> cos 2θ/(1 + sin 2θ)
This is equal to the left hand side.
Thus, it is verified.
Answer:
x<=-5
Step-by-step explanation:
Answer:
y = -6
x = 1
Step-by-step explanation:
-x + 2y = -13
-x - 2y = 11
Sum the equations:
-x -x = -2x
+2y - 2y = 0
-13 + 11 = -2
then
-2x = -2
x = -2/-2
x = 1
from the first eq.
-x + 2y = -13
-1 + 2y = -13
2y = -13 + 1
2y = -12
y = -12/2
y = -6
check:
from the second eq.
-x -2y = 11
-1 -(2*-6) = 11
-1 -(-12) = 11
-1 + 12 = 11
Answer:
D
Step-by-step explanation:
you take away 12 from the total and you'll find how many Zach read (20) then 12+20=32
