y= mx+b
(16, -7) = (x,y)
2(16) - 3y = 12
32 - 3y = 12
32 - 12 = 3y
20/3 = y
6.6 = y
2x-3(-7) = 12
2x+21 = 12
2x = 12 - 21
x = -9/2
Insert the values into y = mx + b
solve for m and then solve for b
You just plug in what Y equals into the second equation:
-2x-3(6x-11) = -7
then you solve the equation:
-2x-18x+33 = -7
-20x+33 = -7
subtract 33 from each side:
-20x = -40
divide each side by -20
x = 2
then you plug x into the original equation:
y = 6(2)-11
y = 12-11
y = 1
so x = 2 and y = 1
This expression is the difference of two cubes:
x^3 y^3
----- - -------
2^3 3^3
The rule here is a^3 - b^3 = (a - b)(a^2 + ab + b^2), so
x^3 y^3 x^2 x^3y^3 y^2
----- - ------- = (x/2 - y/3)*(-------- + ----------- + --------- )
2^3 3^3 2^2 6^3 3^2
Answer:
u r right
Step-by-step explanation:
Answer:
52 dimes and 28 nickels
Step-by-step explanation:
n = number of nickels
d = number of dimes
n+d = 80 the number of coins he got
Multiply the number of nickels times .05 plus the number of dimes times .10 to equal the amount of money he got
.05n + .10d = 6.60
Divide this equation by .05
.05n/.05 + .10/.05 = 6.60/.05
n + 2d = 132
n+d = 80
Multiply by -1
-n-d=-80
Add this to n+2d = 132
n+2d=132
-n-d=-80
-------------------
d = 52
Now we need to solve for n
n+d = 80
n+52 = 80
Subtract 52 from each side
n+52-52= 80-52
n = 28