Answer:
81
Step-by-step explanation:

Answer:
1) 8x
2) 12x - 3y
Step-by-step explanation:
1) Both of them have a like term, so you can subtract them across
2) 10x + 2x = 12x, have a like term so you can add them across and 3y is the outlier so that stays alone.
Hope this helps!
Answer:
12
Step-by-step explanation:
hope it helps
X = Lilys weight
x + 34 = Arthurs weight
4x - 180 = combined weight
x + x + 34 = 4x = 180
2x + 34 = 4x - 180
-2x -2x
_________________
34 = 2x -180
+180 + 180
_______________
214 = 2x
107 = x which is Lily's weight
141 = x + 34 which is Arthur's weight
The total weight is 248
which is the answer that you get when you do 4(107) = 180 or
428 -180 = 248
Tan(x)= sin(x)/cos(x), therefore, substitute sin(x)/cos(x) in the expression:
=(cos(x)(sin(x)/cos(x))-1)/cos^2(x)
simplify the 2 cos(x):
=(sin(x)-1)/cos^2(x)
Sin^2(x)+ cos^2(x)=1, sin^2(x)-1=- cos^2(x), substitute in the expression:
= -cos^2(x)/cos^2(x)= -1