The sum of the left side of these two equations is equal to the same of the right side is these two equations
4x+8y + (-4x+2y) = 20 + 30
10y =50 ( x is eliminated)
y=5
Take this into the second equation
-4x +2y = 30
-4x + 2*5 = 30
x=-5
So x=-5
y=5
Answer:
3 newtons to the left
Step-by-step explanation
since the arrows are pointing towards each other you have to subtract
5-2=3
Since five is the greatest number it will be pushing to the left
Answer:
180
Step-by-step explanation:
180 is the left
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.
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<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.
