What pattern do you see in the powers of 5

The diagram shows a 7cm by 6cm rectangle based pyramid. all the diagonal sides - ta, tb, tc and td are length 10cm. m is midpoint of rectangular base. work out height mt to 1 decimal place

Solve the equation 3x2 + 19x + 9 = 0 to the nearest tenth.

Arrange these numbers from least to greatest 3/5 5/7 2/9