A textbook store sold a combined total of 255 physics and math textbooks in a week. The number of math textbooks sold was 81 less than the number of physics textbooks sold. How many textbooks of each type were sold?

math = 87

physics = 168

Brainliest, please!

Step-by-step explanation:

Variables:

m = math, p = physics

Equations:

m + p = 255

m = p - 81

Substitution:

m + p = 255

(p - 81) + p = 255

2p - 81 = 255

2p = 336

p = 168

Solving for m:

m + p = 255

m + 168 = 255

m = 255 - 168

m = 87

Checking with the other equation:

m = p - 81

87 = 168 - 81

87 = 87

So, math = 87 and physics = 168

Brainliest, please!

walter needs to make at least 5 more cookies but no more than 40. 5 ≤ x ≤ 40

step-by-step explanation:

20 ≤ x + 15 ≤ 55

subtract 15 from all parts

20-15 ≤ x + 15-15 ≤ 55-15

5 ≤ x ≤ 40

this means how many more cookies he has to make

walter needs to make at least 5 more cookies, but no more than 40 cookies; 5 ≤ x ≤ 40