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the cost of X pencils is rupees 50 write the algebraic expressions for the cost of each pencil please step by step explanation और आंसर आना चाहिए 150 बटा 6 |
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Answer» Step-by-step explanation: LET cost of pencil be Rs. x Cost of pens be Rs. y 5 pencils and 7 pens together cost Rs. 50, So we get 5x+7y=50 Subtract 7y both side we get 5x=50–7y Divide by 5 we get
x=10− 5 7
y Plug value of y which is FACTOR of 5 to get WHOLE number so plug y=5,10,15 we get fory=5 x=10− 5 7
y=10−7=3 for y=10 x=10− 5 7
y=10−14=−4 fory=15 x=10− 5 7
y=10−21=−11 Therefore, the REQUIRED points are (3,5),(−4,10),(−11,15). Given that 7 pencils and 5 pens together cost Rs. 46 7x+5y=46 Subtract 7x both side we get 5y=46–7x Divide by 5 we get y=9.2–1.4x Plug x=0,2,4 we get for x=0 y=9.2–0=9.2 for x=2 y=9.2–2.8=6.4 forx=4 y=9.2–5.6=3.6 Therefore, the required points are (0,9.2),(2,6.4),(4,3.6). The graph is as SHOWN below: Since the point of intersection is (3,5), Hence, the cost of one pencil is Rs. 3 and the cost of one pen is Rs. 5 |
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