Answer:
d=62
Step-by-step explanation:
180-56=124
2d=124
Divide both sides by 2
d=62

as a decimal is <span>0.385</span>
Solution:
<u>Simplify the equation and solve for r.</u>
- r/16 + 6 = 7
- => r/16 = 7 - 6
- => r/16 = 1
- => r = 16
The value of r is 16.
<u>Check:</u>
- r/16 + 6 = 7
- => 16/16 + 6 = 7
- => 1 + 6 = 7
- => 7 = 7 (Proved correct)
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.