Respuesta :

Answer:

8. 51

9. 89

10. 20

11. 35

Step-by-step explanation:

sum of the internal angles in a triangle must always total 180 degrees

trick: be careful, sometimes they give you the internal angle, sometimes the external angle

Answer:

question 8........ x =  51 degrees

question 9...... x = 91 degrees

question 10 ........ x = 20 degrees

question 11...... x = 35 degrees

Step-by-step explanation:

Question 8

note : a straight line has angle of 180 degrees

GCE is a straight line hence is 180 degrees

firstly get the angle ECD

which is :

180 - 86 = 94

ECD = 94 degrees

total angle of a triangle is 180 degrees

to get DEC

94 + 35 + x = 180

make x the subject for equation

x = 180 - 35 - 94

x =  51 degrees

Question 9

note : a straight line has angle of 180 degrees

YUW is a straight line hence is 180 degrees

total angle of a triangle is 180 degrees

to find the missing angle ( WUY) ,create an equation

we shall say that angle WUY is Y

29 + 62 +Y = 180

make x the subject of the equation

Y = 180 - 62 -29

Y ( angle WUY) = 89 degrees

now to get the missing angle (?) which will be named as x:

since the straight line is 180 degrees

we say 180 - 89 = 91

x = 91 degrees

Question 10

note : a straight line has angle of 180 degrees

SUZ is a straight line hence is 180 degrees

to get angle SUT is :

180 -80 = 100

angle SUT = 100 degrees

now to get the missing angle (?) we shall name it x

total angle of a triangle is 180 degrees

60 + 100 + x = 180

now make x the subject of formula

x = 180 - 100 - 60

x = 20

Question 11

notice that the angles which are shaped like an X

opposite angles are the same

and since there is a straight line of 180 degrees

180 - 128 = 52 degrees

hence to get the missing angle (x) you have to recall that the total angle of a triangle is 180

hence to get the angle is :

x + 93 + 52 = 180

x = 180 - 52 - 93

x = 35