So technically they are asking you to find the hypotenuse of a right angle triangle the height is 9ft and the length is 3ft so the formula is A² +b²=c²
the a² and B² Being the height and length and label the third side c²
so.. 9²+3²=c² 9×9+3×3=c² 81+9=c² 40=c² √40=√c² 6.32=c therefore the ladder is 6.32
Explanation: In order to solve this, you combine the like terms (variables of the same letter and degree, and constants). (9b+2) + (2b+5) (9b+2b) + (5+2) 11b+7