Question #b03a6

1 Answer
Oct 9, 2017

27^o27o To nearest degree.

Explanation:

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Since it doesn't specify which side is the hypotenuse, the triangle will be marked in the conventional manner, with side c being the hypotenuse.

Because of the large values we will reduce the dimensions by a factor of one hundred. This will not affect the size of the relevant angles .i.e similar triangles.

c^2 = a^2+b^2c2=a2+b2

-> c^2=(4.9)^2+(9.6)^2=116.17=> c=sqrt(116.17)c2=(4.9)2+(9.6)2=116.17c=116.17

Since we now know all three sides and one angle, we can use the Sine Rule:

sinA/a=sinB/b=sinC/csinAa=sinBb=sinCc

We are looking for angle A and we know angle C. So:

sinA/a= sinC/c=> sinA=(asinC)/csinAa=sinCcsinA=asinCc

-> sinA= ((4.9)sin(90))/(sqrt(116.17))=4.9/(sqrt(116.17))sinA=(4.9)sin(90)116.17=4.9116.17

A= arcsin((4.9)/(sqrt(116.17)))=27.04^oA=arcsin(4.9116.17)=27.04o ( 2.d.p.)