Answer:
Part 1) 
Part 2) 
Part 3) 
Part 4) 
Step-by-step explanation:
step 1
Find the length side c
Applying the Pythagoras Theorem

substitute the given values



step 2
Fin the measure of angle B
we know that
In the right triangle

substitute the given values


step 3
Find the measure of angle A
we know that
The measure of interior angles in a triangle must be equal to 180 degrees
so
∠A+∠B+∠C=180°
Remember that in a right triangle the measure of angle C is 90 degrees
we have


substitute


Pythagoras theoram? use it here!
That is,
H² = 15² + 4²
H² = 225 + 16
H = √241
H = 15.5
You should opt for 15.5
P.S: Best of luck for your test! ;))
Answer:
30 gallons of 20% acid solution should be mixed.
Step-by-step explanation:
Let x gallons of a 20% acid solution was mixed with 30 gallons of a 40% solution, to obtain a mixture of 30% acid solution.
Therefore, final volume of the solution will be (x + 30) gallons.
Now concept to solve this question is
20%.(x) + 40%.(30) = 30%.(x + 30)
0.20(x) + 0.40(30) = 0.30(x + 30)
0.20x + 12 = 0.30x + 9
0.30x - 0.20x = 12 - 9
.10x = 3
x = 
x = 30 gallons
Therefore, 30 gallons of the 20% acid solution should be mixed.
Answer:
115
Step-by-step explanation:
The angle is vertically opposite to 115. vertically opposite angles are equal