First term = T(1) is obtained by plugging n = 1 into the formula,
thus First term = 1^2 - 4 = 1 - 4
= 3 (answer)
5x+3y=58
5x-3y=22
(3y gets cancelled bc 3y-3y=0, then add 5x with 5x, so you're left with)
10x=80, (divide both sides by 10)
x=8
Now we look for y. So choose one formula from the two (let's say 5x + 3y=58)
Substitute x for 8 so it will look like---- 5(8)+3y=58
Multiply 5*8--- so you get -- 40+3y=58
Subtract 40 from both sides and you're left with 3y=18
divide both sides by 3
you get y=6
In conclusion, x=8 and y=6 hence, (8,6)
Hey!
so for the first one its 60°, and for the second one its 1/6