Answer:
: c2 = a2 + b2 - 2ab cos C
c²=20²+15²-2×15×20×cos50
c²=400+225-600×0.64
c²=241
c=√241=15.5ft
Slope is -1
Y intercept 3
X Intercept 4
Sorry I do t know the others
Haven’t gone over that
Hope this helps
To do this i add them uo and easily subtract woth a hand held calculator
Answer:
-13a^2 + 170ab - 13b^2.
Step-by-step explanation:
1. 36(a+b)^2 - 49(a-b)^2
This is the difference of 2 squares: a^2 - b^2 = (a + b)(a - b).
36(a+b)^2 - 49(a-b)^2
= (6(a + b) + 7(a - b))( 6(a + b) - 7(a - b))
= (6a + 7a + 6b - 7b)( 6a - 7a + 6b + 7b)
= (13a - b)(-a + 13b)
If you require the expansion of this it is:
-13a^2 + 170ab - 13b^2.