Mathematics · 2020
JEE Main · 4 September 2020, Shift 1 · Q71
If the system of equations x-2 y+3 z =9; 2 x+y+z = b; x-7 y+ a z =24, has infinitely many solutions, then a - b is equal to \ \ \ \.
If the system of equations
$$\begin{aligned}
x-2 y+3 z & =9 \\
2 x+y+z & =\mathrm{b} \\
x-7 y+\mathrm{a} z & =24, \text { has infinitely many }
\end{aligned}
$$
solutions, then $\displaystyle \mathrm{a}-\mathrm{b}$ is equal to \_\_\_\_.
Official answer
5
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JEE Main 2020 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.