<span>2x+y=8
2x+x-7=8
3x=15
x=5
y=5-7
y=-2</span>
Answer:
<h3> in square feet</h3>
Step-by-step explanation:
Area of anything is<u> allways </u>reported <u>in square units</u>. Usually that is square of given unit because it's the simplest way:
R = 50 ft
A = πR² = π•(50 ft)² = π • 50 ft • 50 ft = 2500π ft² ≈ 7854 ft²
{Of course you can re-calculate the units, ex.:
3 feet = 1 yard so 50 ft = 50/3 yd then
A = πR² = π•(50/3 yd)² = π • 50/3 yd • 50/3 yd = 2500/9 π yd² ≈ 872.7 yd² }
You keep the same sign. So:-
4 + 4 = 8 and
--4 + -4 = -8