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Answer:
1/2 a^2, 1/2 b*a , 20, 7.5x^2
Step-by-step explanation:
Area of right angle triangle = 1/2 height * base so
Area of MSP = 1/2 a^2 , Area of BUC =1/2 a*b
Area of BAC =1/2 8*5 , Area of DRK =1/2 3x*5x =1/2 *15x =7.5x^2