Answer:
By comparing the ratios of sides in similar triangles ΔABC and ΔADB,we can say that 
Step-by-step explanation:
Given that ∠ABC=∠ADC, AD=p and DC=q.
Let us take compare Δ ABC and Δ ADB in the attached file , ∠A is common in both triangles
and given ∠ABC=∠ADB=90°
Hence using AA postulate, ΔABC ≈ ΔADB.
Now we will equate respective side ratios in both triangles.

Since we don't know BD , BC let us take first equality and plugin the variables given in respective sides.

Cross multiply

Hence proved.
Answer: 9
Step-by-step explanation:
Two negatives make a positive. So the expression 8-(-1) is equal to 9, because the two subtraction signs the equation create an addition sign, and the equation becomes 8 + 1.
Therefore, 9 has the same value as 8-(-1).
Answer:
m=3, y = 3x - 2
Step-by-step explanation:
slope = rise / run
slope = 6/2
slope = 3
Answer:
13.
Step-by-step explanation:
3x+1
x=4
Substitute x for 4
So, that would be 3*4+1
Now we multiply 3 and 4 to get 12. Then we add in the 1.