Answer:
Average speed = 100 km/h
Step-by-step explanation:
Given:
Total distance covered = 250 km
Total time taken = 8:30 am - 6:00 am = 2:30 hours = 2.5
Find:
Average speed.
Computation:
⇒ Average speed = Total distance covered / Total time taken
⇒ Average speed = 250 / 2.5
⇒ Average speed = 100 km/h
We know the equation of a line is y=mx+b. We know the slope (m) is -2 and all we need is the intercept (b).
Since we know one point, we can plug in 6 for x and 3 for y (along with -2 for m) in our equation and then solve for b.
3= -2*6 + b
3= -12 + b
15 = b
Since we now know the intercept we can now write our equation:
y= -2x + 15
Answer:
See below.
Step-by-step explanation:
ABC is an isosceles triangle with BA = BC.
That makes angles A and C congruent.
ABD is an isosceles triangle with AB = AD.
That makes angles ABD and ADB congruent.
Since m<ABD = 72 deg, then m<ADB = 72 deg.
Angles ADB and CDB are a linear pair which makes them supplementary.
m<ADB + m<BDC = 180 deg
72 deg + m<BDC = 180 deg
m<CDB = 108 deg
In triangle ABD, the sum of the measures of the angles is 180 deg.
m<A + m<ADB + m<ABD = 180 deg
m<A + 72 deg + 72 deg = 180 deg
m<A = 36 deg
m<C = 36 deg
In triangle BCD, the sum of the measures of the angles is 180 deg.
m<CBD + m<C + m<BDC = 180 deg
m<CBD + 36 deg + 108 deg = 180 deg
m<CBD = 36 deg
In triangle CBD, angles C and CBD measure 36 deg making them congruent.
Opposite sides DB and DC are congruent making triangle BCD isosceles.