.hello :
an equation of the circle <span>Center at the w(a,b) and ridus : r is :
(x-a)² +(y-b)² = r²
in this exercice : r = 1
</span><span>The points (-18,15) and (-20,15) lie on a circle with a radius of 1:
</span>(-18-a)²+(15-b)² = 1 ....(1)
(-20-a)² +(15-b)² = 1 ....(2)
solve this system :
(1) -(2) : (-18-a)² - (-20-a)² =0
(-18-a)² =(-20-a)² =0
( -18-a = -20-a) or (-18-a = - (-20-a))
1 ) ( -18-a = -20-a) no solution confused : -18=-20
2 ) -18-a =20+a
-2a =38
a = -19
subst in (1) :(-18+19)²+(15-b)² =1
(15-b)² = 0.... 15-b = 0 .... b = 15
the center is :w(-19,15)
What I understand from the picture given, she had 2 ribbons with the length of 1/4.
These would be the two shortest ones.
So: 1/4 + 1/4 = 2/4
= 1/2
I hope this helps and I know that it is different to what HimyBrainy put but it is what I understood! :/
There is no solution ,<span>a+c=-10;b-c=15;a-2b+c=-5 </span>No solution System of Linear Equations entered : [1] 2a+c=-10
[2] b-c=15
[3] a-2b+c=-5
Equations Simplified or Rearranged :<span><span> [1] 2a + c = -10
</span><span> [2] - c + b = 15
</span><span> [3] a + c - 2b = -5
</span></span>Solve by Substitution :
// Solve equation [3] for the variable c
<span> [3] c = -a + 2b - 5
</span>
// Plug this in for variable c in equation [1]
<span><span> [1] 2a + (-a +2?-5) = -10
</span><span> [1] a = -5
</span></span>
// Plug this in for variable c in equation [2]
<span><span> [2] - (-? +2b-5) + b = 15
</span><span> [2] - b = 10
</span></span>
// Solve equation [2] for the variable ?
<span> [2] ? = b + 10
</span>
// Plug this in for variable ? in equation [1]
<span><span> [1] (? +10) = -5
</span><span> [1] 0 = -15 => NO solution
</span></span><span>No solution</span>
