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$tan=\frac{opos.}{adj.}$

so let s use pithagorean theorem:

a^2+b^2=c^2

a^2+64=68

a=2

oposite of  angle A is a

oposite of  angle B is b

oposite of  angle C is c (hyp.)

$tan=\frac{opos.}{adj.}=\frac28$

x*20/100=1080

find the x 

180-80=100

100/2=50

yes you can :)

$csc=\frac{hyp.}{oposite}=\frac{5}{3} \\ cos=\frac{adj.}{hyp.}$

so we know hyp=5 and oposite=3 let s use pythagorean theorem to find adj :

3^2+x^2=5^2

x=4  

so your adj is 4 and hyp is 5

$cos=\frac{adj.}{hyp.}=\frac45$

$12000 \times(1.06)^t=29280 \\ t-\text{represent year}$

x+y=12 let s solve for x  x=12-y put it in term s of x in the other equation 

2x-3y=4           x=12-y

24-2y-3y=4

-5y=-20

y=4

x=12-y      y=4

x=12-4

x=8

16x-10y=10           16x-10y=10  (plus them together)

-8x-6y=6 (x2)        -16x-12y=12

                               -22y=22 

                                y=-1

put y=-1 into one of the equations(i choosed -8x-6y=6 because it is easier):

-8x-6y=6              y=-1

-8x+6=6

-8x=6-6

-8x=0

x=0