Answer:
6.3feet
Step-by-step explanation:
Given data
Radius= 4feet
The expression for the circumference of a circle is
C= 2πr
Substitute
C=2*3.142*4
C=25.136 feet
Also, a 90° arc is 1/4 of the circumference of a circle
Hence the length of the 90° arc is
=25.136/4
=6.284 feet
=6.3feet
One way in which to approach this problem would be to treat it as an equation of ratios and to cross multiply:
<span>[(4x + 15) / 5x)] = 1/2 could be written as:
4x + 15 1
----------- = ---
5x 2
Then 8x + 30 = 5x
3x = -30, and so x = -10 (answer). Be certain to check this answer through substitution!
</span>
The answer to your question is 20
