Distribute all the negatives: 7a-9c+12a+33c+21a-10c
simplify:
40a+14c
Since one equation has a negative y and the other has a positive y, I'm going to use those since they cancel each other out. Before that, the two y's need to be equal to each other.
x+2y=6
x-y=3
Multiply the bottom equation by two so then you have:
x+2y=6
2x-2y=6
The y's now cancel out:
x=6
2x=6
Add them together
3x=12
Divide
x=4.
To find y, plug x into either equation (*don't have to do both, but I will)
(4)+2y=6
(4)-y=3
Subtract four
2y=2
-y=-1
Divide each
2y/2 = 2/2
y=1
-y/-1 = -1/-1
y=1
The answer is:
x=4
y=1
I hope that helps!
Given CD is an altitude such that AD=BC , AB=3 cm and CD= √2 cm.
Let AD=x, Since given AB=3
AD+DB=3
x+DB = 3
DB = 3-x
Since ΔBCD is rght angle triangle, let's apply Pythagoras theorem
Since given AD=BC,let us plugin BC=x in above step.
6x=11
x=
Now we know AD=x= and given CD=√2.
Let us apply Pythagoras theorem for ΔACD
= 2.315cm
Answer:
Check the ppicture i sent you i think it would help
