Can someone help me with these questions ASAP!!

Step-by-step explanation:

Formula of the circumference of  the circle is 2*pi*r

1.A=pi*r^2=pi*3^2=9pi

2.A=pi*10.8^2=

3.r=14/2=7 so

A=pi*7^2=49pi

4. A=pi*(31/2)^2Km^2=15.5^2*pi

5.  semicircle

 A=pi*16^2/2cm^2=

6.A=pi*(22.6/2)^2=11.3^2*pi

(0,-3) see attached graph

step-by-step explanation:

a. to solve the system, graph the two equations.

x = y+3 becomes y=x-3 has m=1/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move up 1 unit and 1 unit to the right. plot a point and connect.

y=-4x+3 has m =-4/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move down four units and to the right 1 unit. plot a point and connect.

the solution is the point (x,y) where the two lines intersect. by the graph below it is (0,-3).

b. to solve by substitution, substitute y = -4x-3 into x= y+3

x= (-4x-3) +3

x=-4x

5x=0

x=0

now substitute x = 0 back in to find y.

y= -4(0)-3

y=0-3

y=-3

solution is (0,-3)

c. use elimination by adding the equations together.

x-y=3

4x+y=-3

5x=0

x=0

then substitute into one equation to find y.

y=-4(0)-3

y=-3