If <em>a</em> is fixed and <em>b</em>,<em>c</em> are unknowns then the equation <em>b</em>+<em>c</em>=10-<em>a</em> has 11-<em>a</em> solutions. They are pairs (b,c): (0,10-a), (1,9-a), (2,8-a), ... (10-a,0). As <em>a</em> runs from 0 to 10 we have total number of solutions (11-0)+(11-1)+...(11-1)=11+10+...+1=(1+11)*11/2=66.
You almost had it right! remember the equation of a circle is
(x - h)^2 + (y - k)^2 = r^2. the center is (h,k) and r is the radius.
(x - 0)^2 + (y - 0)^2 = 5^2
x^2 + y^2 = 25 <<< your answer
hope that helps, God bless!
Answer:
y=4x-13
Step-by-step explanation:
