That would be choice 3
middle term = -3mn-8mn = -11mn and last term = + 2n^2
Yes I think (A) is the correct answer
Answer:
The measure of ∠EFG is 52°
Step-by-step explanation:
Given line m is parallel to line p. m∠HEF = 39º and m∠IGF = 13º.we have to find m∠EFG.
In ΔJFG,
By angle sum property of triangle, which states that sum of all angles of triangle is 180°
m∠FJG+m∠JGF+m∠JFG=180°
⇒ 39°+13°+m∠JFG=180°
⇒ m∠JFG=180°-39°-13°=128°
As JFE is a straight line ∴ ∠JFG and ∠EFG forms linear pair
⇒ m∠JFG+m∠EFG=180°
⇒ 128°+m∠EFG=180°
⇒ m∠EFG=52°
The measure of ∠EFG is 52°
From the given question we come to know of certain number of facts and they are:
At 1:00 PM the water level of the pond was = 13 inches
At 1:30 PM the water level of the pond was = 18 inches
At 2:30 PM the water level of the pond was = 28 inches
From the above given facts we can easily find the amount of water changing every half an hour.
Amount of increase in water from 1:00PM to 1:30 PM = (18 - 13) inches
= 5 inches
Amount of increase in water level from 1:30PM to 2:30PM = (28 -18) inches
= 10 inches
From the above two deductions we can come to the conclusion the the constant rate of change in water level is 5 inches for every half an hour.