I need help on understanding it and the answers please

Which statement is true? the given sides and angles cannot be used to show similarity by either the sss or sas similarity theorems. the given sides and angles can be used to show similarity by the sss similarity theorem only. the given sides and angles can be used to show similarity by the sas similarity theorem only. the given sides and angles can be used to show similarity by both the sss and sas similarity theorems.

What number should be added to both sides of the equation to complete this square? x^2-10x=7

Afactory buys 10% of its components from suppliers b and the rest from supplier c. it is known that 6% of the components it buys are faulty. of the components brought from suppliers a,9% are faulty and of the components bought from suppliers b, 3% are faulty. find the percentage of components bought from supplier c that are faulty.