kinda left explainitory but I need help with finding the base

Answer:
6.4 cm
Step-by-step explanation:
Area of triangle = 17.28 cm²
[tex]\frac{1}{2}*base *altitude = 17.28\\\\\frac{1}{2}*base*5.4=17.28\\\\base = 17.28*\frac{2}{5.4}\\\\base= 3.2*2\\\\base = 6.4 cm[/tex]