HELP PLEASE HELP!! John checked his answer and found that it was incorrect. John’s work is below. What did he do incorrectly?

ℎ + 10 = 25
ℎ + 10 + 10 = 25 + 10
ℎ = 35
Please list everything he did incorrectly! Thank you!!

Need 50 will mark brainliest answer. find the lengths of all the sides and the measures of the angles.

Aretha wanted to gather data about the cost of local bowling leagues in her area. she plotted the data and determined that the average bowling league costs consist of a one-time registration fee and a monthly fee modeled by the equation y = 15x + 20. identify and interpret the y-intercept in this model. the y-intercept is 20. this is the cost per month. the y-intercept is 20. this is the cost of registration. the y-intercept is 15. this is the cost of registration. the y-intercept is 15. this is the cost per month.

Name two numbers whos difference is -3