The difference between three times a number and 7 is 14

Ascientist has 50 grams of a radioactive element. the amount of radioactive element remaining after t days can be determined using the equation (1) after two days the scientist receives a second shipment of 50 grams of the same element. the equation used to represent the amount of shipment 2 remaining after t days is 10) - 50 which of the following is an equivalent form of the expression for the amount remaining in shipment 2? what’s the answer?

Tatiana reads 40 pages of her book every night for x number of nights. write an expression that shows the number of pages she has read

y=2x−1 5x−4y=1 is (1,1)(1,1) a solution of the system?