Q. −3a+5b6a+2b=11=26Consider the given system of equations. If (a,b) is the solution to the system, then what is the value of ba ?
Multiply Equations: Let's solve the system of equations using the method of substitution or elimination. We will use the elimination method to eliminate one of the variables and solve for the other.First, we need to make the coefficients of one of the variables the same in both equations. We can multiply the first equation by 2 and the second equation by 3 to make the coefficients of a the same.
New System of Equations: After multiplying the first equation by 2, we get:2(−3a+5b)=2(11)−6a+10b=22And after multiplying the second equation by 3, we get:3(6a+2b)=3(26)18a+6b=78Now we have the new system of equations:\begin{cases}-6a+10b=22\18a+6b=78\end{cases}
Add Equations: Next, we add the two equations together to eliminate a:(−6a+10b)+(18a+6b)=22+78This simplifies to:(−6a+18a+10b+6b=100)12a+16b=100
Solve for 'a': Now we can solve for 'a' by isolating it on one side:12a=100−16ba=12100−16b
Substitute 'a': We can substitute the expression for 'a' back into one of the original equations to solve for 'b'. Let's use the first original equation:−3a+5b=11Substituting 'a', we get:−3(12100−16b)+5b=11
Simplify Equation: Now we simplify the equation:−3(12100)+3(1216b)+5b=11−25+(4b)+5b=119b−25=11
Correct Mistake: We made a mistake in the previous step while distributing the −3 across the terms in the parentheses. Let's correct this and simplify again.−3((100−16b)/12)+5b=11−((300−48b)/12)+5b=11−25+4b+5b=11
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