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
So for number 3, so for every 15 he earns, he saves 6 so
15:6=5:2
then he earns 75 and saves x
5 times what=75
5 times 15=75
2 times 15=30
so the ration is 75:30
he saved $30
then
write a real life proportion
so rob has a pattern to make,
for every 5 blue tiles, he puts down, he must put down 7 green tiles,
he needs to fill a sqare area that is 12 feet in legnth and width
each tile is 1 foot
how many blue tiles will he need
so 5+7=12
area=12 times 12
area=144
so the number of tiles is 144
so blue=5/12
so 144 times 5/12=60 blue tiles
I think the answer is -1=x-3<4
Answer:
2√6
Step-by-step explanation:
find the hypotenuse of the triangle thats 3 and 7
pythagorean
3 squared + 7 squared
16 + 49 = 57
√57 is the hypotenuse
√57 is also the base of the triangle that has side thats 9
pythagorean theorem
x squared + √57 squared = 9 squared
x^2 + 57 = 81
x^2 = 81 - 57
x^2 = 24
x = √24
x = √4 * √6
x = 2√6
Answer:
try 7,920 miles
Step-by-step explanation:
I just took 8,578 - 658 and got 7,920.