It looks like your equations are
7M - 2t = -30
5t - 12M = 115
<u>Solving by substitution</u>
Solve either equation for one variable. For example,
7M - 2t = -30 ⇒ t = (7M + 30)/2
Substitute this into the other equation and solve for M.
5 × (7M + 30)/2 - 12M = 115
5 (7M + 30) - 24M = 230
35M + 150 - 24M = 230
11M = 80
M = 80/11
Now solve for t.
t = (7 × (80/11) + 30)/2
t = (560/11 + 30)/2
t = (890/11)/2
t = 445/11
<u>Solving by elimination</u>
Multiply both equations by an appropriate factor to make the coefficients of one of the variables sum to zero. For example,
7M - 2t = -30 ⇒ -10t + 35M = -150 … (multiply by 5)
5t - 12M = 115 ⇒ 10t - 24M = 230 … (multiply by 2)
Now combining the equations eliminates the t terms, and
(-10t + 35M) + (10t - 24M) = -150 + 230
11M = 80
M = 80/11
It follows that
7 × (80/11) - 2t = -30
560/11 - 2t = -30
2t = 890/11
t = 445/11
Answer: Ola
Step-by-step explanation:
Answer:
Step-by-step explanation:
Michael and Juanita are interested in the amount of sand required to build a sand pyramid of the size that they see while at a sand sculpture exhibit. They carefully measure the width of the square base of the sand pyramid which is 4 feet and the height of the pyramid which is 5 feet. How much sand is required to build this sand pyramid?
Answer:
Step-by-step explanation:
prime factorization
40y³ = 2³×5y³
625 = 5⁴
Greatest common factor = 5
40y³ - 625 = 5(8y³ - 125)
Note that 8y³ - 125 is the difference of cubes.
8y³ - 125 = (2y)³ - 5³ = (2y-5)((2y)² + 2y·5 + 5²) = (2y-5)(4y² + 10y + 25)
40y³ - 625 = 5(2y-5)(4y² + 10y + 25)