Plug in x = 7. Then use the order of operations (PEMDAS) to simplify
y = 11 - 5*x
y = 11 - 5*7 .... x has been replaced with 7 (since x = 7 is given)
y = 11 - 35
y = -24
Total volume is volumes of both square pyramids.
Volume of a tetrahedron is 1/3 times corresponding prism, and a square pyramid has two tetrahedrons.
Thus, volume of on square pyramid:
Since there are two of them, total volume is:
$\boxed{\frac{2a^2b}{3}}$
Are you supposed to estimate or get an exact answer? If you're estimating you can see if the number is close to any perfect squares. In this case 63 is very close to 64, and 48 is very close to 49. The answers can then be estimated to be approximately 8 and 7, respectively.
Answer:
Step-by-step explanation: 4(5)-12 = 20 -12= 8