It depends on what variable you are tying to solve for first. Say you are trying to solve for x first and then y on the first problem you wrote.
In substitution you solve one of the equations for example with
6x+2y=-10
2x+2y=-10
you solve 2x+2y=-10 for x
2x+2y=-10
-2y = -2y (what you do to one side of the = you do to the other)
2x=-10-2y (to get the variable by its self you divide the # and the variable)
/2=/2 (-10/2=-5 and -2y/2= -y or -1y, they are the same either way)
x=-5-y
now you put that in your original equation that you didn't solve for:
6(-5-y)+2y=-10 solve for that
-30-6y+2y=-10 combine like terms
-30-4y=-10 get the y alone and to do this you first get the -30 away from it
+30=+30
-4y=20 divide the -4 from each side
/-4=/-4 (20/-4=-5)
y=-5
now the equation you previously solved for x can be solved for y.
x=-5-y
x=-5-(-5) a minus parenthesis negative -(- gives you a positive
-5+5=0
x=0
and now we have solved the problem. x=0 and y=-5
Answer:
Step-by-step explanation:
To calculate the speed of each one we proceed as follows:
speed=distance/time
a] Noah's speed:
distance=2.5 miles
time=3/5 hours
speed=(2 1/2)/(3/5)
=(5/2)/(3/5)
=5/2×5/3
=25/6
=4 1/6 mi/hr
Emily's speed
distance=3 3/4 miles
time=5/6 hour
thus
speed=(3 3/4)/(5/6)
=15/4)/(5/6)
=15/4×6/5
=4 1/2 mi/hr
Anna's speed:
distance=3 1/3 miles
time=3/5
speed=(3 1/3)/(3/5
=(10/3)/(3/5)
=10/3×5/3
=5 5/9 mi/hr
Anna was the fastest
A square has 4 equal sides which make up the perimeter.
Therefore the length of one side = (16x + 32y) / 4 = 4x + 8y Answer
