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4 votes
Help me solve this equation and show work

11d + 17b = 95
d + b = 7

User Roiberg
by
4.1k points

2 Answers

2 votes

Answer:

B = 3

d = 4

Explanation:

You can use elimination method. Multiply (d + b = 7) by -11.

11d + 17b = 95

-11d - 11b = -77

add together. D’s will cancel

6b = 18

divide by 6

b = 3

plug in 3 for b in the equation of your choice

d + (3) = 7

subtract 3

d = 4

User UndergroundFox
by
4.9k points
6 votes

Answer:

{d,b}={4,3}

Explanation:

[1] 11d + 17b = 95

[2] d + b = 7

Graphic Representation of the Equations :

17b + 11d = 95 b + d = 7

Solve by Substitution :

// Solve equation [2] for the variable b

[2] b = -d + 7

// Plug this in for variable b in equation [1]

[1] 11d + 17•(-d +7) = 95

[1] -6d = -24

// Solve equation [1] for the variable d

[1] 6d = 24

[1] d = 4

// By now we know this much :

d = 4

b = -d+7

// Use the d value to solve for b

b = -(4)+7 = 3

Solution :

{d,b} = {4,3}

User Unikorn
by
4.8k points