Given that abcd is a rhombus what is the value of c 3x+7

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

With this question! what is process of elimination? ? p.s. my brothers acc got banned so add his new one @ yamauchiyamyam17

The transitive property of equality states that: o if a = b, then bra o if a = b, then ac = bc o if a = b and b= c, then a = if a = b and c= c, then a + b = b + c