The first 5 Multiples of 7<span> are 35, 70, 105, 140, 175
</span>The first 5<span> Multiples of </span>20<span> are: </span>20<span>, 40, 60, 80, 100
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Sin (a+b) = sin a. cos b + cos a. sin b
a= 50° and b=40°, then
sin(50+40) = sin 50° . cos 40° + cos 50° . sin 40°
sin(50+40) = sin 90° = 1 and
sin 50° . cos 40° + cos 50° . sin 40° = 1
The formula for finding the area of a trapezoid is: sum of bases*height*1/2
By plugging in the information that we already have, we know: (119+65)*height*1/2=5658
184*1/2*height=5658
92*height=5658
height=61.5cm.
Check:
119+65=184
184*61.5=11316
11316*1/2=5658
all you have to do is see whether both variables of each point meet both contraints:
for a) 1<3 and 2>1 is true so a is a solution to the system
