How do you solve this system of equations in graphing format
16c+10d=720
d=2c

Use the radius you found in part i (r=26.8 cm) with the surface area formula below to find the surface area of the sphere. show your work and round your answer to the nearest tenth. the surface area of a sphere: sa = 4πr^2 self note: 3.8.4

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Ihave trouble finding the nth term of a linear sequence