Simple Algebra problem. Includes the x and y axis. Also need help finding the perimeter.
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Answer:
31.5cm²
Step-by-step explanation:
area of a triangle =1/2 b h
b= 7cm
h=9cm
1/2×7×9
= 1/2×63
= 31.5cm²
hypotenuse is unknown so,
c²=a²+b²
c²= 7² + 9²
= 49 + 81
c²= 130
c= 11.4cm
perimeter= 7 +9+11.4
=27.4cm
pls note that no unit was stated