Multiply first equation by -5 and 2nd by 2, add them
15x+20y=-100
<u>2x-20y=32 +</u>
17x+0y=-68
17x=-68
divide both sides by 17
x=-4
the x value is -4
Think the 4 less than but not equal to as a equal sign
step 1. isolate the variable ( variable must stand alone)
step 2. subtract 12n -12n=0
step 3. since you subtract 12n from the left you must do the same to the right.
step 4. 13n - 12n =1n
step 5. the equation should look like this -4 less than but not equal to 1n
step 6. isolate the variable n
step 6. divide 1n/1 on the right and on the left -4/1 it equals -4
so, n is -4
Answer:
D is the answer. because their are three scalene triangles