You can focus on the two sub-triangles ABC and ACD
We know that they are both right triangles, because we're given that AC and BD are perpendicular.
The sides AB and AD are the hypothenuses of these triangles, so we know their length through the pythagorean theorem:
But since we're given 
, the expressions for AD and AB are actually the same expression. This proves that AD=AB, and thus that the triangle is isosceles.
To be able to compare the rates, we will write them in fraction form.
The fraction that represents Joe's rate is:
and the fraction that represents Bob's rate is:
Simplifying the above fractions, we get:
Since:
then Bob and Joe did not work at the same rate.
Answer:
No, Bob and Joe did not work at the same rate.
Answer: a: 8.25 b: 49.5
Step-by-step explanation:
The length and width of the television could be any two numbers whose product is 70.
