Question

t-3u=61 ; t-u=7 solve it by elimination method​

Answer 1

Answer:

t=-20, u=-27

Step-by-step explanation:

(t-u=7)3

3t-3u=21---1

t-3u=61---2

subtracting 2 from 1

2t=-40

t=-20

-20-u=7

-u=27

u=-27

Answer 2

Step-by-step explanation:

Multiplying equation (ii) by 3

So,

t - 3u = 61......(i)

3t - 3u = 21 ......(ii)

Subtracting the equations as follows :-

$t - 3u = 61 \\{ \underline{ - 3t + 3u = - 7}} \\ \implies \: - 2t = 40 \\ \implies \: t = \frac{40}{ - 2} \\ \implies \: t = - 20 \: ans.$

Substitution of the value of u in the eq.....(i)

⟹ t - u = 7

⟹ -20 - u = 7

⟹ -20 - 7 = u

⟹ -27 = u

⟹ u = -27 ans.