Answer: c. At least 30 of them are spayed or neutered.
Step-by-step explanation:
Answer:
A. (2, -1)
Step-by-step explanation:
(4x - 9) - x = -3
3x - 9 = - 3
3x = 6
x = 2
y = 4(2) - 9
y = 8 -9
y = - 1
(2, -1)
Check
-1 - 2 = -3
Let f be amount of 43% and s be amount of 16%...
s+f=90, f=90-s
(.16s+.43f)/90=.25 using f found above we get:
(.16s+.43(90-s))/90=.25
.16s+38.7-.43s=22.5
-.27s=-16.2
s=60, and since f=90-s, f=30
So the chemist will need to mix 60ml of 16% solution with 30ml of 43% solution to create 90ml of a 25% solution.
Answer:
The radius of the circles are
and 
Step-by-step explanation:
Let
x-----> the radius of larger circle
y----> the radius of smaller circle
we know that

-----> equation A
Remember that
-----> equation B
substitute equation B in equation A and solve for y





Find the value of x


therefore
The radius of the circles are
and 