3x + y = -1
2x + 3y = 18

Step-by-step explanation:

Multiply by -3 the upper equation to make y equal in value but with opposite signs.

Now add equation 1 and 2.

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Solve for x;

To isolate x, divide by -7

Now use one of the equations above and replace the value of x.

To prove if it's correct, take either equation and replace both x and y values, if the results are equal to each other, it is correct.

so a parallelogram is just like a square base times height. multiply 40 and 39 to get 1560 inches.

a triangle is base times height divided by two. so multiply 7.9 and 5 and then divide it by 2 to get 19.75inches.

the kite can be split into two separate triangles and added together to get the total area. 30 x 4 /2 which equals 60. make sure to double it for the two triangles making 120.

on monday rodney ate 1/4th of the sandwich = 3/12

on tuesday he ate 1/3rd of the sandwich = 4/12

therefore in total he has eaten = 3/12 + 4/12 = 7/12

thus we can say that he has eaten 7/12 of the sandwich on monday and tuesday alltogether.

happy to

pls mark as brainliest.