It would equal 5.20043337 but rounded to the tenths would be 5.2 I think
The answer for your question is
3x2=6
6 sq.ft
X = 180 - 104 - 22 = 180 - 126 = 54 degrees
y = 180 - 54 = 126 degrees
z = 180 - 126 - 19 = 180 - 145 = 35 degrees
It is given that
a+b=20 -------------------- (1)
b+c=30 -----------------------(2)
We have to calculate
3 a + 4 b +7 c
Now multiplying equation(1 )by 3,we get
3 a+ 3 b=60 ----------------------------------(3)
and Multiplying equation( 2) by 4,we get
4 b + 4 c=120 -----------------------------------(4)
Adding expression (3) and (4),we get i.e left hand side of 3 to left hand side of 4 and right hand side of 3 to right hand side of 4.
3 a+ 3 b+ 4 b+ 4 c=60+120
Adding like terms, we get
3 a+ 7 b+ 4 c =180, Which is the required solution.
Y = f(x) = cos(x)
= cos(180)
= -1