Answer:
x=3 and y=2
Step-by-step explanation:
1.) 4x+3(5x-13)=18
expand into 4x+15x-39=18
18+39= 57
15x+4x= 19x
57/19= 3 so x=3
substitute 3 into y= 5x - 13
and you get 2 so y=2
<span>tan(15) =
sin(15) / cos(15) =
sin(45 - 30) / cos(45 - 30) =
[ sin(45)cos(30) - sin(30)cos(45) ] / [ cos(45)cos(30) + sin(45)sin(30)]
Since sin(45) = cos(45) = √2/2, you can just factor that out from the top and bottom
[ cos(30) - sin(30) ] / [ cos(30) + sin(30)]
[ √3/2 - 1/2 ] / [ √3/2 + 1/2]
(√3 - 1) / (√3 + 1)
(√3 - 1)^2 / (√3+1)(√3 - 1)
(√3 - 1)^2 / (3 - 1)
(3 - 2√3 +1) / 2
2 - √3
There's also a formula for tan(a-b), but I couldn't remember it off hand.</span>
Answer:
It's kinda hard to see can you type out the question?
Step-by-step explanation:
Since the lines a and b are parallel, <4 and <8 are of the same measure. To find <8, we can simply subtract the measure of <7 from 180 degrees.
<4 = <8 = 180 - <7 = 180- 114 = 66 degrees