Is there a picture that goes along with this question.
Distance=speed times time
if they take the same time, we cal the time , t
b=bike speed
w=walking speed
bikedistnace=17=bt
walkdistance=9=wt
b is 4 more than w
b=4+w
we have
17=bt
9=wt
b=4w
ok so
multiply first equation by 9 and 2nd by 17
153=9bt
153=17wt
set equal
9bt=17wt
divide both sides by t
9b=17w
sub b=4+w for b
9(4+w)=17w
distribute
36+9w=17w
minus 9w both sides
36=8w
divide both sides by 8
4.5=w
he walks 4.5kph
Answer:
y = 20°
x = 35°
Explanation:
Equation's:
1) 2y + x + 105° = 180°
2) 3x + x + 2y = 180°
Make y subject in equation 2
3x + x + 2y = 180
4x + 2y = 180
2y = 180 - 4x
y = 90 - 2x
Insert this into equation 1
2(90 - 2x) + x + 105° = 180°
180 - 4x + x + 105 = 180
-3x = -105
x = 35°
Find value of y
y = 90 - 2x
y = 90 - 2(35)
y = 20°
The answer is b. There is a proof, but it is easily got by proving the other cases wrong.
