Answer:
A
Step-by-step explanation:
Using Pythagoras' identity in the right triangle.
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
BC² = 9² + 12² = 81 + 144 = 225 ( take the square root of both sides )
BC = 
= 15 → A
Answer:
z = 70
Step-by-step explanation:
Explanation: To solve this proportion for z, we can use cross products.
When we get the equation 5z = 350, we can get z by itself on the left side of the equation by dividing both sides of the equation by 5. On the left, the 5's cancel each other out and we have z. On the right, 350 divided by 5 simplifies to 70 so we have z = 70.
