Answer:
Step-by-step explanation:
d = r * t
Let the time at 59 miles / hour be t
59*t + 57* (4.5 - t) = 259.5 Remove the brackets
59*t + 256.5 - 57*t = 259.5 Combine the left
2t + 256.5 = 259.5 Subtract 228 from both sides
2t = 259.5 - 256.5 Combine
2t = 3 Divide by 2
t = 1.5
So he spent 1.5 hours going at 59 miles per hour
He spent 4.5 - 1.5 = 3 hours going 57 miles per hour.
Answer:cos(53), cos 53 degrees
Step-by-step explanation: sin(angle)= cos(90-angle)
sin(37)=cos(90-37)=cos(53)
Answer:
33.16ft
Step-by-step explanation:
Sin 56° = x / 40ft
0.829 = x / 40ft
x = 40ft * 0.829
x = 33.16ft
Answer
2802.833
Step-by-step explanation:
Answer:
See explanation
Step-by-step explanation:
In ΔABC, m∠B = m∠C.
BH is angle B bisector, then by definition of angle bisector
∠CBH ≅ ∠HBK
m∠CBH = m∠HBK = 1/2m∠B
CK is angle C bisector, then by definition of angle bisector
∠BCK ≅ ∠KCH
m∠BCK = m∠KCH = 1/2m∠C
Since m∠B = m∠C, then
m∠CBH = m∠HBK = 1/2m∠B = 1/2m∠C = m∠BCK = m∠KCH (*)
Consider triangles CBH and BCK. In these triangles,
- ∠CBH ≅ ∠BCK (from equality (*));
- ∠HCB ≅ ∠KBC, because m∠B = m∠C;
- BC ≅CB by reflexive property.
So, triangles CBH and BCK are congruent by ASA postulate.
Congruent triangles have congruent corresponding sides, hence
BH ≅ CK.