Write an algebraic expression for... 15 more than w

*An algebraic expression is a mathematical phrase that can contain numbers, variables (letters) and operations (+, -, x ÷)

Television sizes are based on the length of the diagonal of the television's rectangular screen. so, for example, a 70-inch television is a television having a diagonal screen length of 70 inches. if a 70 inch television's diagonal forms a 29°angle with the base of the screen, what is the vertical height (1) of the screen to the nearest inch? 70 inhin

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?