find x. pls answer with explanation
Answers
Ola there! hope this helps. btw explanation is in italics.
1)
we know that (from exterior angle property) all exterior angles = 360 degree
therefore,
(4x-5) + (4x+20) + (x) + (5x-5)= 360 (then we add all like terms)
(4x+4x+x+5x) + ( -5 + 20 -5) = 360 ( I am using brackets so that its easier for u to understand no need for them in ur notebook)
14x + 10 = 360
( 4x+ 4x= 8x then add 5x = 13x then add 1x= 14x, 20 + (-5) +(-5)= 20 + (-10) = 10)
14x= 360- 10 (transverse +10 to the other side it becomes -10)
14x= 350
x= 350/14 ( 14 was multiplying on the lhs so it will devide on rhs)
x=25
the first answer without explanation:
(4x-5) + (4x+20) + (x) + (5x-5)= 360
(4x+4x+x+5x) + ( -5 + 20 -5) = 360
14x + 10 = 360
14x= 360- 10
14x= 350
x= 350/14
x=25
2)
we know that sum of all angles of a quadrilateral ( a figure with 4 sides) is 360 degree ( the angle sum property)
therefore,
25 + 40+ 20+x= 360
85 +x =360 ( transverse 85 to right hand side)
x= 360 - 85
x= 275