Since the big triangle is an isosceles one, we conclude that the angles of the left triangle are: 32, 90 and 3x-10. Sinche the sum of this angles have to be 180° we have:

Solving for x, we have:

Therefore, x=22.67 and the answer is A.
Answer:
about 2.47
Step-by-step explanation:
Your calculator will tell you ...

Answer:
Read it and do your best
Step-by-step explanation:
440 gallons of 80 % antifreeze solution must be mixed with 80 gallons of 15% antifreeze to get a mixture that is 70% antifreeze
<em><u>Solution:</u></em>
Let "x" be the gallons of 80 % antifreeze added
Therefore, "x" gallons of 80 % antifreeze solution must be mixed with 80 gallons of 15% antifreeze
Final mixture is x + 80
Therefore, we can frame a equation as:
"x" gallons of 80 % antifreeze solution must be mixed with 80 gallons of 15% antifreeze to get (x + 80) gallons of 70 % antifreeze
Thus, we get,
x gallons of 80 % + 80 gallons of 15 % = (x + 80) gallons of 70 %

Thus 440 gallons of 80 % antifreeze solution must be mixed
Both of them together have 690 because you subtract 152 from 421 so...
421-152=269
Then add 269 to 421
421+269=690