Answer:
11
Step-by-step explanation:
The two equations appear to be ...
- 12x +4y = 152
- 32x +12y = 420
These can be solved for y using Cramer's rule:
y = (152(32) -420(12))/(4(32) -12(12)) = -176/-16 = 11
The cost of the vegetarian lunch is 11.
_____
<em>Comment on Cramer's Rule</em>
For equations ...
ax +by =c
dx +ey = f
The solutions are ...
x = (bf -ey)/(bd -ea)
y = (cd -fa)/(bd -ea) . . . . note the denominators are the same expression
Once you memorize the pattern of products, this can be the simplest way to solve a pair of equations--especially if you only need one of the variable values.
Answer:
length = 14 m
width = 7 m
Step-by-step explanation:
l = length
w = width
l = 2w - 8
w(2w - 8) = 42
2w² - 8w - 42 = 0
you can factor out a 2 to work with smaller numbers:
w² - 4w - 21 = 0
(w - 7)(w + 3) = 0
w = 7
'w' cannot equal a negative so we discount it as an answer
find length:
l = 2(7) - 8
l = 14 - 8 or 6m
The graph of a quadratic equation is a U-shaped curved called parabola. It is because the parabola makes very easy to find the axis of symmetry to plot selected points and finding the roots and vertex.
Good luck :)
Answer:
the length of the thread remaining is 790 cm
Step-by-step explanation:
Given;
original length of the thread, L₀ = 10 m = 1000 cm
the length of the thread used, L₁ = 210 cm
The length of the thread remaining is calculated as follows;
ΔL = L₀ - L₁
ΔL = 1000 cm - 210 cm
ΔL = 790 cm
Therefore, the length of the thread remaining is 790 cm
The answer is -2. The line is going from left to right which makes it negative. Then if you look at the line and do change in y(rise) over change in x(run).
