Each exterior angle of a regular 25-gon = 360/25 = 14.4 deg. and each interior angle= 165.6 deg.
4y+2x=14 ==> multiply this 1st equation by (-1) => -4y-2x=-14
Now add it up to the 2nd equation
-4y-2x=-14
2y+2x=10
-------------- And now add them up
-2y +0x=-4
==> -2y=-4==> 2y = 4 & y=2
Last step: plug y into any equation & you will find x=3
The answer would be -7.
7 - (-4) - 18 (Simplify 3 * (-6) to -18)
7 + 4 - 18 ( Simplify brackets )
-7 (Simplify).
This can be solver by creating a small equation with x being the number and solving for x. The equation would be 8 + 2( x + 3 ) = -6
Solve for x:
8 + 2( x + 3 ) = -6
Distribute the 2
8+ (2x+6)=-6
Subtract 8
2x+6= -14
Add 6
2x= 8
Divide by 2
x=4
So the number you are looking for is 4
I hope this helps!
All but c are correct so the answer is a b and d
