Answer :
Tammy completed 12 jobs.
What is the substitution method?
The algebraic approach to solving simultaneous linear equations is known as the substitution method. in this procedure, The value of one variable from one equation is substituted in the second equation.
Given Susanne(S) did 10 jobs, and three girls together did 28 jobs Tammy(T) works twice as fast as Martha(M).
Since the girls each worked for two hours, this indicates that Tammy worked twice as much or held twice as many jobs.
T = 2M ........................equation (1)
M + S + T = 28 ........................equation(2)
S = 10 ..................................equation(3)
By solving the above equation, we get:
Martha(M) = 6
Tammy(T) = 12
Hence, Tammy completed 12 jobs.
To know more about the substitution method refer to: https://brainly.com/question/10606449
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