-9x-6y=15
9x-10y=145
Find y first by eliminating the x.
Add the two equations together.
-9x+9x-6y+-10y=15+145
-6y+-10y=15+145
-6y-10y=160
-16y=160
divide both sides by -16 to get +y
-16y/-16=160/-16
y=-10
Use the substitution method to find x
-9x-6y=15
-9x-6(-10)=15
Do the bracket first
-9x+60=15
Move +60 to the other side. Sign changes from +60 to -60.
-9x+60-60=15-60
-9x=-45
Divide both sides by -9
-9x/-9=-45/-9
x=5
Answer:
( 5,-10)
Answer:
7-5x
Step-by-step explanation:
Answer:
8...I want these points lol
Step-by-step explanation:
Step-by-step explanation:
factor 4 out of the variable terms, as this helps.
but my approach is simply to define the target and then calculate "backwards".
we want to find
(ax + b)² = a²x² + 2abx + b²
and now we compare with the original equation :
a²x² = 4x²
a² = 4
a = 2
2abx = 16x
2×2×bx = 16x
4b = 16
b = 4
b² = 16, but we have only 3, so we need to subtract 16-3 = 13 from the completed square.
so, our equation is
(2x + 4)² - 13 = 0
(2x + 4)² = 13
2x + 4 = sqrt(13)
2x = sqrt(13) - 4
x = sqrt(13)/2 - 2
