Answer:
We use addition because -16 is negative, and we need to cancel out its value so we add 16 to both sides, leaving 0+x, or x, on the left and combining like terms on the right.
Step-by-step explanation:
Multiply 1st equation by 5
-5x + 10y = -20
now you have
-5x + 10y = -20
5x - 10y = 20
---------------------add
0 + 0 = 0
0 = 0
answer
C. the system has infinitely many solutions
What the heck do you mean??????????
Let the distance of Jill form the base of the tower be x, then tan 40 = 100/x
x = 100/tan 40 = 100/0.8391 = 119.18 meters
Let the height of the tower from the level of the top of Jill's apartment be y, then tan 30 = y/119.18
y = 119.18 x tan 30 = 68.8 meters
Therefore, the height of Jill's apartment is 100 - 68.8 = 31.2 meters
I’m very confused what are you trying to do here ?