We need to solve -3x+4y=12 for x
Let's start by adding -4y to both sides
-3x+4y-4y=12-4y
-3x=-4y+12
x = (-4y+12)/-3
x= 4/3 y -4
Now substitute 4/3 y -4 for x in 1/4 x - 1/3 y =1
1/4 x -1/3 y =1
1/4 (4/3 y -4) -1/3 y =1
Use the distributive property
(1/4)(4/3 y) + (1/4)(-4) -1/3 y =1
1/3 y -1 - 1/3 y =1
Now combine like terms
(1/3y -1/3y) + (-1) =1
= -1
-1 = 1
Now add 1 to both sides
0=2
So there are no Solutions
The answer is C
I hope that's help Will :)
Answer:
95 square units
Step-by-step explanation:
Surface area of pyramid = 4(side area) + base
Solve for the base first.
Area of base = s*s = 5*5 = 25
Next solve for one of the sides.
Area of triangle = 1/2 b*h = 1/2 5*7 = 17.5
Plug these back into our original equation.
Surface area of pyramid = 4(side area) + base
Surface area of pyramid = 4(17.5) + 25
Surface area of pyramid = 70 + 25 = 95 square units
386 divided by 20 is 19.3 so Greg averaged 19.3 miles per gallon.
Answer:
45
Step-by-step explanation:
AEF is a similar triangle to ABC. that means it has the same angles, and the sides (and all other lines in the triangle) are scaled from the ABC length to the AEF length by the same factor f.
now, what is f ?
we know this from the relation of AC to FA.
FA = 12 mm
AC = 12 + 28 = 40 mm
so, going from AC to FA we multiply AC by f so that
AC × f = FA
40 × f = 12
f = 12/40 = 3/10
all other sides, heights, ... if ABC translate to their smaller counterparts in AEF by that multiplication with f (= 3/10).
the area of a triangle is
baseline × height / 2
aABC = 500
and because of the similarity we don't need to calculate the side and height in absolute numbers. we can use the relative sizes by referring to the original dimensions and the scaling factor f.
baseline small = baseline large × f
height small = height large × f
we know that
baseline large × height large / 2 = 500
baseline large × height large = 1000
aAEF = baseline small × height small / 2 =
= baseline large × f × height large × f / 2 =
= baseline large × height large × f² / 2 =
= 1000 × f² / 2 = 500 × f² = 500 ×(3/10)² =
= 500 × 9/100 = 5 × 9 = 45 mm²
