Step-by-step answer:
Please refer to attached image.
1. Quad PQRS is cyclic (all vertices on the same circle), so opposite angles are supplementary, meaning
that
angles QPS and QRS are supplementary =>
QPS+QRS=180 =>
QRS = 180 - 74 = 106
2. Triangle RSQ is isosceles with RS=RQ =>
angles RSQ and RQS are congruent.
3. Angle RSQ = (180 - 106) /2 = 74 / 2 = 37
4. QP is a diameter => angle QSP is a right-angle.
5. From (3) and (4) above,
angle RSP = 37+90 = 127
6. Since PQRS is cyclic, angles RQP and RSP are supplementary =>
RQP+RSP = 180 =>
x + 127 = 180 =>
x = 180 - 127 = 53 degrees.
First way
arcsin(1/4) means that 1/4 sin of the angle.
sin(α)=1/4
sin²α+cos²α=1
(1/4)²+cos²α=1
cos²α=1-1/16 =15/16
cosα=+/-(√15)/4
<span>Second way
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sin(α)=1/4 =opposite leg/hipotenuse
cos(α)=adjacent leg/hypothenuse
adjacent leg =√(hypotenuse²- Opposite²)=√(16-1)=√15
cosα=+/-√15/4
For one value of sinα, possible 2 values of cosα.
This is the concept of algebra, the solution of the given expression will be given as follows;
-5x+2x²=-6x
adding 5x on both sides we get
5x-5x+2x²=-6x+5x
2x²=-x
divide both sides by 2
(2x²)/2=-x/2
x²=-x/2
divide both sides by x
(x²)/x=-x/(2x)
x=-1/2
the answer is x=-1/2