7. 4x+y=8 ----- first equation
(+)
-3x-y=0
_______
x = 8 ---- second equation
substitude second equation into first equation
4(8) + y = 8
32 + y = 8
y = 24
8. 2x+5y=20 ---- first equation
(-)
2x-5y =3
________
10y = 17
y = 17/10 ---- second equation
substitude second equation into first equation
2x + 5(17/10) = 20
2x + 17/2 = 20
4x + 17 = 40
4x = 23
x = 23/4
9. 3x+2y=-10 (×2) ---- first equation
2x-5y=3 (×3)
6x + 4y = - 20
(-)
6x - 15y = 9
___________
19y = - 29
y = - 29/19 ---- second equation
substitude second equation into first equation
3x + 2(-29/19) = - 10
3x - 58/19 = - 10
3x = - 132/19
x = - 44/19
We know that the Angle subtended by an arc on centre of the circle is double as that of Angle subtended by the same arc on the circumference (boundary) of the circle
So,
Answer:
Step-by-step explanation:
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5/8 - 17/8
combine : 5-17 / 8
subtract : 5 - 7 = -12
-12/8
apply fraction rule ( -a/b = - a/b) : - 12/8
cancel common factor 4
answer : - 3/2
I hope this helped