A lab technician has 40 gallons of a 15% iodine solution. How many gallons of a 40% iodine solution must he add to make a 20% iodine solution?

Please show work!!

Idon’t understand! use slope intercept form to solve: through: (2,5) slope= undefined

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

Acompany charges $0.10 for each letter engraved. bobby plans to spend no more than $5.00 on the engraving on a jewelry box. write and solve an inequality to find the maximum number of letters he can have engraved.