Answer:
and 
Step-by-step explanation:
when you solve for r in the given equation, you need to apply the square root property, which gives positive and negative answers (both should therefore be considered):

then you need to include these two possible solutions:
and 
Answer:
Step-by-step explanation:
x + 40 = 10
x = -30
She paid $30 on her credit card
Answer:
9
Step-by-step explanation:
3 x 3 =9 9 divived by 1
9
20 is the size of a random sample of 720 marbles.
Notice that 720=20*36
If there are 2 yellow marbles in the sample of 20 marbles, then we can expect:
2*36=72 yellow marbles in the box of 720 marbles
So, B) 72 is the correct answer
Answer:
right triangle
isosceles triangle
Step-by-step explanation:
The box in the corner means that this triangle is a right triangle. It is a 90 degree angle
We know this is an isosceles triangle since the two sides have the lines on them. Those marks means it has the same side length.