1.37x + 1.08y = 16.36
x + y = 13
x = 13 - y
1.37* (13-y) + 1.08y = 16.36
17.81 - 1.37y + 1.08y = 16.36
1.08y - 1.37y = 16.36 - 17.81
-0.29y = -1.45
y = 5
x + 5 = 13
x = 13-5
x = 8
He bought 8 notebooks and 5 book covers
The easiest way to do this is to plot the points. I used the pythagorean theorem for this one, too. Add the side lengths to get the perimeter: 5 + 5 + 5 + 3 + √40 = 24.32455532 units or just 24 units.
Answer:
when they
Step-by-step explanation:
equal the same value when you break them up
100 3/4 x 75 1/2
25 x 3 x 75 1/2. (Divided by 4 to 100 and 4 to get 25)
25 x 3 x 75 1/2 ( multiple everything on top)
5625/2 ( then divided normally)
2812.5 or 2812 1/2
Answer:
The solution to the system is S= (-2, -4).
Step-by-step explanation:
Given the system
−4x+5y=−12
x−6y=22
The first step is to solve x from the first equation for example, and substitute the expression in the second equation.
1) -4x + 5 y = -12 ⇒ -4x = -12 - 5y ⇒ x = (-12 - 5y)/-4 ⇒ x = 3 + (5/4)y
2) x - 6y = 22 ⇒ (3 + (5/4)y) - 6y = 22 ⇒ 3 + (5/4)y - 6y = 22
⇒ 3 - (19/4)y = 22 ⇒ (-19/4)y = 22- 3 ⇒ y = 19/(-19/4) ⇒ y =-4.
Finally, with the value obtained for "y", you have to return to the original equations and replace it to obtain the "x" value.
-4x + 5y = -12 ⇒ -4x + 5(-4) = -12 ⇒ -4x - 20 = -12 ⇒ -4x = -12 + 20
⇒ -4x = 8 ⇒ x = 8/-4 ⇒ x = -2.
Summarizing, the solution to this system is S = (-2, -4).