Please help will give 50points
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Answer:
a=10
Step-by-step explanation:
Using Pythagoras theorem
[tex] {(a + 2)}^{2} + {( a- 5)}^{2} = {(a + 3)}^{2} [/tex]
[tex] {a}^{2} + 4a + 4 + {a}^{2} - 10a + 25 = {a}^{2} + 6a + 9[/tex]
simplify:
[tex] {a}^{2} - 12a + 20 = 0[/tex]
(a-2)(a-10)=0
hence a= 2 or a=10 however we must reject 2 as the lengths of the triangle cannot be negative eg. the side for a-5 will be equivalent to -3 cm which is not possible for lengths to become negative