Answer:
17cm
Step-by-step explanation:
The formula for the area [tex]\sf (A)[/tex] of a trapezium is given by:
[tex]\sf A = \dfrac{1}{2}h(a + b) [/tex]
where:
In this case, the area [tex]\sf (A)[/tex] = 34 cm² and the height ([tex]\sf h[/tex]) is 4 cm.
Let [tex]\sf a[/tex] and [tex]\sf b[/tex] represent the lengths of the two parallel sides.
[tex]\sf 34 = \dfrac{1}{2}(4)(a + b) [/tex]
Now, solve for [tex]\sf a + b[/tex]:
[tex]\sf 34 = 2(a + b) [/tex]
[tex]\sf 17 = a + b [/tex]
So, the sum of the parallel sides [tex]\sf (a + b)[/tex] is 17 cm.