Answer:
I can help with Q "4" as -
It uses triangle congruence test - here we use - SAS, as
one side is equal as it is given
both the angles are 90 degree
and they share a same side
so -
8x = 6x + 5
8x - 6x = 5
2x = 5
x = 2.5
RU = 6x+ 5 = 6 (2.5) + 5 = 20
( I am not so sure but I think this is the answer )
M<J = m<N ( alternate angles)
m<K = m<M ( alternate angles)
so the third angles must also be equal ( total 180 degrees in each triangle)
Therefor the triangles are similar
The answer would be 21 because its the same length as the other side.
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