Area of a triangle = 1/2 b•h
A = 1/2 b • h
A = 1/2 (10 cm • 9 cm)
A = 1/2 (90 cm^2)
A = 45 cm^2.
Its (a) 28 ÷ b = 7 Because When we divide 28 roses in each bunch consisting 7 roses therefore there are 4 bunch of roses therefore the equation (a) satisfy the result and the variable b has value 4.
You can find the slope using the following formula:
Cos(A-B) = cosAcosB + sinAsinB
<span>
cos(</span>π/2 - θ) = cos(π/2)cosθ + sin(π/2)sinθ
π/2 = 90°
cos(π/2) = cos90° = 0. sin(π/2) = sin90° = 1
cos(π/2 - θ) = cos(π/2)cosθ + sin(π/2)sin<span>θ
</span>
= 0*cosθ + 1*sin<span>θ = </span>sin<span>θ
Therefore </span>cos(π/2 - θ) = sin<span>θ
QED </span>
