Brigitte cleans out the loose change from the cup holder in her car (pennies, nickels, and dimes). she finds three more nickels than dimes, and six more pennies than twice the number of nickels. if the total value of the coins is $2.31, how many of each coin did she have in her cup holder? it needs to be solved using linear equations of three variables and i don't understand how to do that.

With these 5 geometry questions! pls 1.)quadrilateral abcd is inscribed in this circle. what is the measure of ∠a ? enter your answer in the box.°2.)quadrilateral abcd is inscribed in a circle. what is the measure of angle a? enter your answer in the box. m∠a= 3.)quadrilateral abcd is inscribed in this circle. what is the measure of angle b? enter your answer in the box. m∠b= °4.)quadrilateral abcd is inscribed in this circle. what is the measure of angle a? enter your answer in the box.°5.) quadrilateral abcd is inscribed in this circle. what is the measure of angle c? enter your answer in the box.°