Angle A = 3x - 10
Angle B = x
Their angle sum = 90° ( complementary angles form 90° )
This can be written in an equation as =
= 3x - 10 + x = 90
= 3x + × + ( -10 ) = 90
= 4x + (-10) = 90
= 4x = 90 + 10 ( transposing-10 from LHS to RHS changes-10 to +10 )
= 4x = 100
= x = 100 ÷ 4 ( transposing ×4 from LHS to RHS changes ×4 to ÷4 )
= x = 25
Angle A = 3x - 10
= 3 × 25 - 10
= 75 - 10
= Angle A = 65°
Angle B = x = 25°
Their sum = 65 + 25 = 90°
Therefore , the complementary angles , Angle A = 65° and Angle B = 25° .
Percent sold=sold/original times 100
sold=816
original=850
percent sold=816/850 times 100
percent sold=0.96 times 100
percent sold=96%
We are given an equation:

This is an equation of a circle. General form of a circle equation is:

Where:
a = x coordinate of a center
b = y coordinate of a center
r = radius of a circle
Motion detector can detect person anywhere within a boundary. The greatest distance at which detector can detect is at the edge of a circle. That distance, between detector and edge of circle, is equal to radius.
From the equation we have:

The greatest distance at which person can be detected is 4ft.
The answer is A if I am correct